Yes, that's the editor I started working with.
I don't know how close the map loading code is compared to everything else. I rewrote a bunch of it to work with virtual file streams (e.g., NAS2D's FileIO functions built on top of PhysicsFS), modified some of the interfaces and cleaned up some of the code that I considered broken. I don't remember exactly what I changed, it's been awhile since I really looked at it (September me thinks?).