Not a very big deal - but i flew a wyrm into the castle...but a zelous pikeman attacked me and switched spots with me - so AI had a pikeman on the castle...
next turn his pikeman attacked my wyrm from on the castle, which should have ended the game as me winner - but it didnt
just minor
actually that could be working as intended because you didn't actually "move" onto the castle.
also if your wyrm dies when entering the castle square it's not a win