Can anyone tell me how to make a polar dimension?
First, make sure the room you want to be polar-dimension style is using the Warp Zone tileset. Open your level file (*.vvvvvv) with a text editor. Scroll down until you find text that looks something like this:
<edLevelClass tileset="3" tilecol="X" platx1="_" platy1="_" platx2="_" platy2="_" platv="4" enemyx1="_" enemyy1="_" enemyx2="_" enemyy2="_" enemytype="_" warpdir="_">Y</edLevelClass>
What "_" is depends on the room. "X" is what you want to change.
Make sure that Y is the same as the name of your room! If it isn't, you're editing the wrong room. Each edLevelClass line represents the data for a room in your level.
Change X (whatever it is) to 6. If your room has no name, give it a temporary one so you can find it. Using the Find feature with your roomname as the text will make things quicker.
Repeat this for all the rooms in the polar dimension.