diff --git a/bumpversion.sh b/bumpversion.sh
index 31ebf154b..ac6116bcc 100644
--- a/bumpversion.sh
+++ b/bumpversion.sh
@@ -17,9 +17,11 @@
 
 # Parse arguments.
 newversion="$1"
+romversion="$2"
+
 if [ -z "$(echo "$newversion" | grep '\.')" ]
 then
-	echo '[!] Usage: bumpversion.sh x.y[.z]'
+	echo '[!] Usage: bumpversion.sh x.y[.z] [romversion]'
 	exit 1
 fi
 shift
@@ -30,6 +32,12 @@ newversion_min=$(echo "$newversion" | cut -d. -f2)
 newversion_patch=$(echo "$newversion" | cut -d. -f3)
 [ -z "$newversion_patch" ] && newversion_patch=0
 
+if [ -z "${romversion}" ]; then
+	# Get the latest ROM release from the GitHub API.
+	romversion=$(curl --silent "https://api.github.com/repos/86Box/roms/releases/latest" |
+		grep '"tag_name":' |
+		sed -E 's/.*"([^"]+)".*/\1/')
+fi
 
 # Switch to the repository root directory.
 cd "$(dirname "$0")" || exit
@@ -61,6 +69,7 @@ patch_file src/include_make/*/version.h EMU_VERSION_PATCH 's/(#\s*define\s+EMU_V
 patch_file src/include_make/*/version.h COPYRIGHT_YEAR 's/(#\s*define\s+COPYRIGHT_YEAR\s+)[0-9]+/\1'"$(date +%Y)"'/'
 patch_file src/include_make/*/version.h EMU_DOCS_URL 's/(#\s*define\s+EMU_DOCS_URL\s+"https:\/\/[^\/]+\/en\/v)[^\/]+/\1'"$newversion_maj.$newversion_min"'/'
 patch_file src/unix/assets/*.spec Version 's/(Version:\s+)[0-9].+/\1'"$newversion"'/'
+patch_file src/unix/assets/*.spec '%global romver' 's/(^%global\ romver\s+)[0-9]{8}/\1'"$romversion"'/'
 patch_file src/unix/assets/*.spec 'changelog version' 's/(^[*]\s.*>\s+)[0-9].+/\1'"$newversion"-1'/'
 patch_file src/unix/assets/*.spec 'changelog date' 's/(^[*]\s)[a-zA-Z]{3}\s[a-zA-Z]{3}\s[0-9]{2}\s[0-9]{4}/\1'"$(pretty_date)"'/'
 patch_file src/unix/assets/*.metainfo.xml release 's/(<release version=")[^"]+(" date=")[^"]+/\1'"$newversion"'\2'"$(date +%Y-%m-%d)"'/'
diff --git a/src/86box.c b/src/86box.c
index deded3382..56847b2a9 100644
--- a/src/86box.c
+++ b/src/86box.c
@@ -138,6 +138,10 @@ char	rom_path[1024] = { '\0'};		/* (O) full path to ROMs */
 rom_path_t rom_paths = { "", NULL };    /* (O) full paths to ROMs */
 char	log_path[1024] = { '\0'};		/* (O) full path of logfile */
 char	vm_name[1024]  = { '\0'};		/* (O) display name of the VM */
+#ifdef USE_INSTRUMENT
+uint8_t instru_enabled = 0;
+uint64_t instru_run_ms = 0;
+#endif
 
 /* Configuration values. */
 int window_remember;
@@ -567,6 +571,12 @@ usage:
 
 			/* .. and then exit. */
 			return(0);
+#ifdef USE_INSTRUMENT
+		} else if (!strcasecmp(argv[c], "--instrument")) {
+			if ((c+1) == argc) goto usage;
+			instru_enabled = 1;
+			sscanf(argv[++c], "%llu", &instru_run_ms);
+#endif
 		}
 
 		/* Uhm... out of options here.. */
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 1420aaa89..428d5b521 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -57,6 +57,10 @@ if(VNC)
     endif()
 endif()
 
+if(INSTRUMENT)
+    add_compile_definitions(USE_INSTRUMENT)
+endif()
+
 target_link_libraries(86Box cpu chipset mch dev mem fdd game cdrom zip mo hdd
     net print scsi sio snd vid voodoo plat ui)
 
diff --git a/src/include/86box/86box.h b/src/include/86box/86box.h
index ca7fbb99c..30a7542dc 100644
--- a/src/include/86box/86box.h
+++ b/src/include/86box/86box.h
@@ -76,6 +76,10 @@ extern uint64_t source_hwnd;
 extern char rom_path[1024]; /* (O) full path to ROMs */
 extern char log_path[1024]; /* (O) full path of logfile */
 extern char vm_name[1024];  /* (O) display name of the VM */
+#ifdef USE_INSTRUMENT
+extern uint8_t instru_enabled;
+extern uint64_t instru_run_ms;
+#endif
 
 #define window_x monitor_settings[0].mon_window_x
 #define window_y monitor_settings[0].mon_window_y
diff --git a/src/nvr.c b/src/nvr.c
index b73aa6fa7..a68331e34 100644
--- a/src/nvr.c
+++ b/src/nvr.c
@@ -237,6 +237,7 @@ nvr_load(void)
 {
     char *path;
     FILE *fp;
+    uint8_t	regs[NVR_MAXSIZE] = { 0 };
 
     /* Make sure we have been initialized. */
     if (saved_nvr == NULL) return(0);
@@ -255,9 +256,12 @@ nvr_load(void)
 	fp = plat_fopen(path, "rb");
 	saved_nvr->is_new = (fp == NULL);
 	if (fp != NULL) {
+        memcpy(regs, saved_nvr->regs, sizeof(regs));
 		/* Read NVR contents from file. */
-		if (fread(saved_nvr->regs, 1, saved_nvr->size, fp) != saved_nvr->size)
-			fatal("nvr_load(): Error reading data\n");
+		if (fread(saved_nvr->regs, 1, saved_nvr->size, fp) != saved_nvr->size) {
+			memcpy(saved_nvr->regs, regs, sizeof(regs));
+            saved_nvr->is_new = 1;
+        }
 		(void)fclose(fp);
 	}
     } else
diff --git a/src/qt/evdev_mouse.cpp b/src/qt/evdev_mouse.cpp
index 120f4572c..5ad252f1a 100644
--- a/src/qt/evdev_mouse.cpp
+++ b/src/qt/evdev_mouse.cpp
@@ -31,6 +31,7 @@ extern "C"
 #include <86box/86box.h>
 #include <86box/plat.h>
 #include <86box/mouse.h>
+#include <poll.h>
 }
 
 static std::vector<std::pair<int, libevdev*>> evdev_mice;
@@ -54,25 +55,39 @@ void evdev_mouse_poll()
 
 void evdev_thread_func()
 {
+    struct pollfd *pfds = (struct pollfd*)calloc(evdev_mice.size(), sizeof(struct pollfd));
+    for (unsigned int i = 0; i < evdev_mice.size(); i++)
+    {
+        pfds[i].fd = libevdev_get_fd(evdev_mice[i].second);
+        pfds[i].events = POLLIN;
+    }
+
     while (!stopped)
     {
+        poll(pfds, evdev_mice.size(), 500);
         for (unsigned int i = 0; i < evdev_mice.size(); i++)
         {
             struct input_event ev;
-            int rc = libevdev_next_event(evdev_mice[i].second, LIBEVDEV_READ_FLAG_NORMAL, &ev);
-            if (rc == 0 && ev.type == EV_REL && mouse_capture)
-            {
-                if (ev.code == REL_X) evdev_mouse_rel_x += ev.value;
-                if (ev.code == REL_Y) evdev_mouse_rel_y += ev.value;
+            if (pfds[i].revents & POLLIN) {
+                while (libevdev_next_event(evdev_mice[i].second, LIBEVDEV_READ_FLAG_NORMAL, &ev) == 0)
+                {
+                    if (ev.type == EV_REL && mouse_capture)
+                    {
+                        if (ev.code == REL_X) evdev_mouse_rel_x += ev.value;
+                        if (ev.code == REL_Y) evdev_mouse_rel_y += ev.value;
+                    }
+                }
             }
         }
     }
+
     for (unsigned int i = 0; i < evdev_mice.size(); i++)
     {
         libevdev_free(evdev_mice[i].second);
         evdev_mice[i].second = nullptr;
         close(evdev_mice[i].first);
     }
+    free(pfds);
     evdev_mice.clear();
 }
 
diff --git a/src/qt/qt_main.cpp b/src/qt/qt_main.cpp
index a74958511..694a0e5f6 100644
--- a/src/qt/qt_main.cpp
+++ b/src/qt/qt_main.cpp
@@ -109,9 +109,21 @@ main_thread_fn()
             if (drawits > 50)
                 drawits = 0;
 
+#ifdef USE_INSTRUMENT
+            uint64_t start_time = elapsed_timer.nsecsElapsed();
+#endif
             /* Run a block of code. */
             pc_run();
 
+#ifdef USE_INSTRUMENT
+            if (instru_enabled) {
+                uint64_t elapsed_us = (elapsed_timer.nsecsElapsed() - start_time) / 1000;
+                uint64_t total_elapsed_ms = (uint64_t)((double)tsc / cpu_s->rspeed * 1000);
+                printf("[instrument] %llu, %llu\n", total_elapsed_ms, elapsed_us);
+                if (instru_run_ms && total_elapsed_ms >= instru_run_ms)
+                    break;
+            }
+#endif
             /* Every 200 frames we save the machine status. */
             if (++frames >= 200 && nvr_dosave) {
                 qt_nvr_save();
diff --git a/src/qt/qt_openglrenderer.cpp b/src/qt/qt_openglrenderer.cpp
index 3a5f58846..cce5b5014 100644
--- a/src/qt/qt_openglrenderer.cpp
+++ b/src/qt/qt_openglrenderer.cpp
@@ -95,8 +95,8 @@ OpenGLRenderer::resizeEvent(QResizeEvent *event)
     context->makeCurrent(this);
 
     glViewport(
-        destination.x(),
-        destination.y(),
+        destination.x() * devicePixelRatio(),
+        destination.y() * devicePixelRatio(),
         destination.width() * devicePixelRatio(),
         destination.height() * devicePixelRatio());
 }
@@ -179,8 +179,8 @@ OpenGLRenderer::initialize()
         glClearColor(0.f, 0.f, 0.f, 1.f);
 
         glViewport(
-            destination.x(),
-            destination.y(),
+            destination.x() * devicePixelRatio(),
+            destination.y() * devicePixelRatio(),
             destination.width() * devicePixelRatio(),
             destination.height() * devicePixelRatio());
 
@@ -425,6 +425,14 @@ OpenGLRenderer::onBlit(int buf_idx, int x, int y, int w, int h)
 
     context->makeCurrent(this);
 
+#ifdef Q_OS_MACOS
+    glViewport(
+        destination.x() * devicePixelRatio(),
+        destination.y() * devicePixelRatio(),
+        destination.width() * devicePixelRatio(),
+        destination.height() * devicePixelRatio());
+#endif
+
     if (source.width() != w || source.height() != h) {
         source.setRect(0, 0, w, h);
 
diff --git a/src/unix/assets/86Box.spec b/src/unix/assets/86Box.spec
index d5fe0a0b1..585e1aa17 100644
--- a/src/unix/assets/86Box.spec
+++ b/src/unix/assets/86Box.spec
@@ -12,6 +12,8 @@
 # After a successful build, you can install the RPMs as follows:
 #  sudo dnf install RPMS/$(uname -m)/86Box-3* RPMS/noarch/86Box-roms*
 
+%global romver v3.7
+
 Name:		86Box
 Version:	3.7.1
 Release:	1%{?dist}
@@ -20,7 +22,7 @@ License:	GPLv2+
 URL:		https://86box.net
 
 Source0:	https://github.com/86Box/86Box/archive/refs/tags/v%%{version}.tar.gz
-Source1:	https://github.com/86Box/roms/archive/refs/tags/%{version}.tar.gz
+Source1:	https://github.com/86Box/roms/archive/refs/tags/%{romver}.zip
 
 BuildRequires: cmake
 BuildRequires: desktop-file-utils
@@ -55,7 +57,7 @@ It supports various models of PCs, graphics and sound cards, and CPUs.
 
 %package	roms
 Summary:	ROMs for use with 86Box
-Version:	%{version}
+Version:	%{romver}
 License:	Proprietary
 BuildArch:	noarch
 
@@ -111,7 +113,7 @@ popd
 
 # files part of the rom package
 %files roms
-%license  roms-%{version}/LICENSE
+%license  roms-%{romver}/LICENSE
 %{_datadir}/%{name}/roms
 
 %changelog