So even though you have relations with these women - you will in the end have to choose just 1 of them, do you then leave the rest with nothing?
Seems to me that he should become a king marry Gwen and have several mistresses ie: Freja, Val, Isha, the sisters etc...
yeaaaaaaah no, having the last scene be a pick one of five doesn't give the impression of it being a harem and that's ok, i just ask of you to clear that up
If you GPU drivers are up to date, try changing Ren'py's renderer. Hold down shift while launching the game and try selecting "Force ANGLE2 renderer", since the error message seems to indicate an error with GL rendering.
I had those issues with the most recent versions in the OP at the moment. 1.0.3ns for season 1 and 2.0.11ns for season 2.
I kept playing till the end of that version for season 2 and found more problems. A pretty obvious one was during the scene with Valery in the castle dungeon, it jumped to an animation with Freja and then back to Valery.