I’ve just discovered a frankly huge bug after it came roughly one button press from losing me about 24 hours of work. As far as I can tell I have a 100% replication rate.
I’ve been alternating working on this model between 2 machines so when I loaded it up on my main machine I was presented with a message informing me that this file was read-only as it had been locked. I have no idea why this happened but I went with it.
Trying to access an unlocked version I then hit File>Save As. Save As is important here as it is VERY DIFFERENT from Save As a Copy. After hitting Save As I figured I’d replace the read-only version of my file with a new open one so I used the same name and hit replace. Only to find out that the save would not work, as the file was read only.
Only to find out that Sketchup had still ‘replaced’ the old file, leaving me without the .skp file I was working on.
TL;DR using Save As on a read-only file when saving as something with the same name and hitting replace only serves to delete your file.
EDIT: SketchUp 2015, Windows 7.