I've lost a complete project (1.7 kB)! only because of a bug within AI2. The story is that I used the right mouse button to duplicate an extended block. This lead to a glued mouse pointer at that block so that I couldn't free the mouse pointer from that block releasing the left button. So I decided to reload AI2 and the result is what you can see in the picture. The issue of a caught/glued mouse pointer already appeared several times in the past, it could be solved by restarting AI2, this time, so far, not! In the past I reported diverse errors/bugs concerning the blocks panel. Now I'm going to stop using AI2. Don't know what really happened. In the farer past there didn't appear errors like that (as well as others). AI2 is not reliable usable. This event is really irritating.
This URL allows you to open AI2 to the Project List, without opening any project.
http://ai2.appinventor.mit.edu/?autoload=false
From that list, you can request Exports of Projects without trying to open them.
Upload the troublesome .aia here.
Maybe it can be saved?