Okay, I see. Well, it could also be a null pointer issue… the code that does the record is called by a timer callback that gets canceled and causes a dialog popup when you press save. If the timer were to fire again after it was previously stopped this could cause an issue. But, I explicitly cancel the timer on the stop button being pressed. However, another event could be in the queue and get processed.
That said, I don’t have this problem on any machine I’ve tested which includes Macs, Mac VMs, Raspberry Pi, Windows PC, Windows VMs, Linux boxes, linux VMs, etc. Note that I use windows 10. The default folder path should be the documents folder.
Anyway, you can change the folder that gets opened by default by editing an INI file setting:
C:\Users<username>\AppData\Roaming\OpenMV\OpenMVIDE.ini
Make sure this says:
[OpenMVFFMPEG]
LastSaveVideoPath=C:/Users//Desktop/video.mp4