I encountered problems with corrupted files a few versions ago. The problem for me was recurring when I had Construct running while the PC was left off for a lot of hours with out doing anything. Sometimes the next save was corrupted and most (if not all) of the textures was missing (I used the compressed .capx save option). The "solution" was a lot of iterative saves. That was before the autosave functionality though.
Try searching "Particles.png" at the Textures folder within your Project folder. If there isn't there, put a png image with the same name and see if that helps.
Also, try the autosave file, perhaps it has most of your work intact.