That is fixed by adding anything (e.g. a comment) into the room creation code - the deal is that GM will "link" the RCC in the room file when you click the button, it removes the RCC file if it's empty, but it does not unlink the file from the room file, so to GMLive it looks like your project is missing files (well, it's impossible to tell in this case). I'll make this not error in the next release.