Hello Jay! Sorry you had to encounter that, but thank you very much for reporting it. I'm assuming that since you wrote "finally got around to playing 0.5" you're using an old save from 0.4.1?
I did my best to avoid compatibility issues with old versions but that one may have slipped. This is the first time I've heard of this bug, so let me know just in case so I can find out how to replicate it.