@yaomon17. I found the issue. In the animation 'Spellsmith_DS', at this time: https://dl.dropboxusercontent.com/u/257 ... lslash.PNG
You have an image that was removed from the directory, but is still referenced in the project. If you change this to a different image, or add a file called "SpellSmith_DualAttackSlash0000.png" to the directory it should import fine.
In prior versions Spriter would create an image file that looked like the missing image symbol, but that was causing issues when users edited a file with older software and trying to refresh in Spriter would cause a valid image to get overwritten.
I added a few related things to Spriter's to do list though, because now that it doesn't create the files automatically, it should warn you on exit, list missing file names and ask if you want to generate the missing file pngs.