Woah, this is comprehensive analysis on the bug to say the least! :D
You're right on the source of the bug. After the tormented one battle, blood golem stays in your party because the game is missing the function that removes him. When you open the menu, blood golem got no portrait graphics and that causes the crash.
I should put a disclaimer somewhere on how to evade this bug until I get the the update out. In short, if possible don't use blood golem in that fight or if you do, don't open menu until you've been in one fight after that.
I have already fixed the bug, but since it's so cumbersome to update the game currently, I've been postponing the release of the next update. I'm trying to have it out by the 21st of this month. The update will bring some bigger changes to the game too and additional areas, enemies and items.
And I'm really glad you're enjoying the game despite it's occasional technical shortcoming! And million dollars huh? :D That's a goal......................................