Re-downloaded via a link in posted in this topic and while the wallet was syncing the blockchain it might have crashed again and somehow managed to take down the entire flash drive with it, which has seemingly been corrupted completely now (trying to recover the data but it's not looking good). Due to my restricted knowledge I can't really report anymore details (or even find out how this actually happened) to maybe help the devs to find a bug or something..
So I at least wanted to report my experience and that I think the Mac wallet might still not be entirely stable yet.
Other than that I'm looking forward to the future development of BTX!
Did you choose to store blockchain on USB drive as well?