Oh I didn't notice there were updates after I've played the game.
Hmmm... none of them seems to mention my issues so I'm going to post my issues here.
1. I can't purchase key here:
I can do that in 2 other shops though.
2. I can't get this reward:
3. In rooms with jumping enemies (bunnies and winged demon which spawns bats when attacked), they could jump out of screen north and never return. I had to leave and reenter the room to get them.
There's another thing, I don't know if it's glitch or not: picking up time stop in a room/map with hiding enemies (orange wizards and spiky burrowers) will kill them, or at least makes the game think that I've defeated them. In room with rewards for killing all enemies, the above glitch will reward me.
I have small doubt cause there's a room with 2 orange wizards and I picked time stop from one of them. I left the room and returned to find the remaining orange wizard is there.
Also after taking the second sword, white rocks appeared which could be destroyed with that sword. Yet similar white rock near entrance of level 5 couldn't be destroyed. I'm not sure if that's intended or not.