I run Alpha v0,799 of the escapists and can't upgrade because of the way I downloaded it - it happened to my sister and twice with me, I just keep a working file of the game on my USB so if it breaks (which it hasn't done in a while) I can reinstall, though you will lose progress. Mine lost all speech apart from rollcall names, guards yelling and peoples names, and I couldn't do favours. The title screen boxes were blank, but I know how to navigate the menu so I was fine. I don't know if this bug is still in the latest version, I will be downloading soon hopefully as I want to try the map editor, and the original post was 3 months ago, so I don't know if it's sorted itself out in that time.
If you paid money for the game and can't reinstall without spending money, I suggest you contact steam or the alternative buyer where applicable, but it's not advisory to buy (pay for) the game from anywhere other than Steam.
Hopefully this helps, if it's not already sorted!