First of all, congrats on the release!
Count me in among those who wait for a Linux build. In the meantime I've tried it with Wine, but I'm getting the same "FATAL ERRORS" like others have reported in other threads. Downloading the data.zip file and extracting it at C:\Users\<YOUR USER>\AppData\Local\AdventurOS\data didn't help. :\
Also, the game seems to perform an update check at startup, and it gets stuck "Loading..." if there's no internet connection available. Could you check that and skip the update step if no network is found, or after a certain timeout?