Yeah I played it for a while and for an alpha release it's not bad, it has a lot of potential, it does have game breaking bugs though, memory leaks and as you said, saving is broken, which is game breaking considering you don't really want to invest too much time unless you don't mind losing everything ( or crashing if and once memory leak destroys your game ). But they are aware of these issues and are looking to fix them ASAP.
It will be especially fun in the future once they finish the core of the game and then add in co-op.