I did that, I got this non-consistent issue with the plugin reading from temp (causes the no image red box)instead of the project folder. I'm pretty much aware of updating it from the folder.
[QUOTE=Squidget]For changes that don't involve adding/changing the sprite images themselves, you can just remove the .scon and .scml files from the C2 project and reimport the latest versions. Much faster.[/QUOTE]
That is how I did it.
Edit: I think I get what my problem now, it seems working directly with dropbox folder will give this inconsistency problem. So far everything is ok after I moved my project folder to desktop instead.