After a bit of trial and error, I found that the following import and export settings are needed to get DBPro to load .X files and materials together without it crashing.
The following needs to be ticked, and everything else unticked :
The bitmap needs to be saved as a bitmap using the same name as that used in the Material Manager. This means that bhoodiNUT, dirtyNUT, and Shaders cant be used, which is a bit of a shame as some of these are quite good.
Yes, I really am THAT good...