I can't upload either.
"Zip contains file extensions not on the whitelist"
I double checked families, and the whitelist, but nothing... I suppose I should email the game, because Tom must be asleep now...
Make sure you export your game into an empty folder.
I got the same problem once. Something strange happens when exporting Arcade Zip into a folder with other content. It seemes to include other files/folders that are in the same folder as export!