Thanks for respond TGG, good questions.
My block has absolutely nothing to do with any of the map classes. I'm not subclassing anything out of the ordinary, just BlockContainer, ModelBase, TileEntity and TileEntitySpecialRenderer. My item renderer implements IItemRenderer without extending anything at all and it's a really simple class.
I checked to see if it looks like a map in all views and it does not. It only looks like a map in first-person view when it's being held in your hands. The view where you would normally read a map. It looks fine in third person, on the ground, in the inventory, etc.
I saw this in the recent change log for forge:
ml
Added a RenderType that allows Map-style rendering w/o inheriting from
ItemMap.
Unfortunately, I just started working with forge a week ago and I don't know my way around the library (or even eclipse) enough to figure out with any speed if that is the cause of my current dilemma. I'll be trying your suggested method for a while. Let me know if you think of anything. Thanks again, I appreciate it.