I'm not seeing any error when I import that project into App Inventor. Can you let us know what browser and operating system you're using in case the error is platform specific?
Edit: Never mind. The issue is due to a new block variation we added. The format of the block text changed and we only updated the English string only. This is resulting in projects containing the block in question to fail to load in other languages. I have prepared a fix that's being reviewed. As a temporary workaround you can switch App Inventor into English until we deploy the fix.