So I had issues getting the mod to work properly, I tried everything in the list of the pinned thread and still a no go the floors flat out where not showing up. I then uninstalled all 3 required mods, started and exited the game, re installed all 3 mods, started and exited the game, went back in again and still a no go on the new floors. But then I tried something else, I tried instead of starting a Isaac run I tried starting as one of the new characters instead, it then came up with the info screen and everything and then finally the new floors showed up, I then exited the run and started up an Isaac run and low and behold it finally loaded the floors for the defualt characters as well.

So if you are having issues with getting to the new floors and have tried everything in the pinned thread, I would suggest trying to start a new run with a new character to get the rest of the mod to load up, that is what fixed the issue for me.