Hi,
thanks for playing! Which door do you mean - the one in the levels, or the doors in the dungeon menu? In the dungeon menu, it is intended that you cannot visit a room you have already cleared...maybe this needs to be made more obvious.
The animations and the "end turn button" problem are among the next things I'm working on - unfortunately, I ran out of time during the jam. Until the jam is over, I'm not allowed to upload any changes to the game, but when it's over, I'll upload a new version with these features. :-)
Yeah, more advanced features, including more chess pieces, or additional rules will definitely be included in upcoming versions! The instant attack once you move in the attack range of a piece sounds like an interesting mechanic. However, in this version, your chess pieces only take damage when you move (1 damage for each move), or when it's the enemy's turn, and he attacks your pieces.
Thanks again for your feedback!