Weird Boss Door issue

Level 1 everything's peachy keen, but once I got to level 2, the boss door is wide open, and while the boss spawns just fine and drops the heart contained, the two shutters in the boss room are already open when you enter, so you can skip right to the triforce chamber if you just run across. What am I doing wrong?

(Unrelated: I was trying to get a bombable wall to connect to another room with a corresponding bombable wall but for some reason the bomb only seemed to open it on one side, making it impossible to walk to the next room)

(This is on 1.5.1)

Hi.

Do you have that room type as "boss room" and that Maps Dmap set to the same Lv. as another Dmap? Bosses are unique to each Lv IIRC. (edit: this might only relate to the actual boss enemy now that I think about it. Are you setting the doors via F6 as "NES Dungeon" (see below), or are you doing Freeform dungeons?)

Not sure about the second one... strange. Is the door type set up as in "NES dungeon" or just combos? (F6 to set NES doors)

I'm using F6 doors for the bombable walls and the actual doors, like the shutters and boss doors mentioned.

Thoooough I just checked the DMap and it was set for 'interior' instead of 'NES Dungeon' So could that have been the issue?

Edit: Yup. That was it! Fixed both problems. Though now I have to wonder how to use boss doors in a freeform dungeon. Is it just impossible?