Which (Windows 10, Windows 11, Steam Deck) are you using?
If you are downloading or updating the game, ensuring you have the build is vital. Playing the raw v0.3 version almost guarantees a crash during the mid-game transition. The patched version provides: princess+reconquista+v03+sorry+karl+patched
The developer quickly pivoted, releasing a hotfix specifically addressed to these progression blocks. The "Sorry Karl" tag became the official (and somewhat humorous) nickname for the patch. Which (Windows 10, Windows 11, Steam Deck) are you using