I am having an issue with a SW part model not keeping it's Material call out even after saving the model.

I've assigned a material to this model then saved it. I have a drawing that references this model. When I look at the title block space where the material is supposed to be displayed says "Material ". I go to the model to check what is up and lo and behold the model also says "Material ". I can edit the material in the model to bring things back in order, but as soon as I try to bring this drawing up again the same thing happens. Has anyone seen this type of behavior? I have very similar parts/drawings of this kind that work perfectly. Does anyone have a clue to what could be happening?

Here are some particulars:

• I am using SW 2011 x64 SP5.0
• The part has NO configurations
• The model has a custom property called "Material" which is linked to the value: SW-Material@@DEFAULT@MD2E620ZM8.SLDPRT
• It is a multi-body model (don't know if this can be a factor)