MSH files are automaticly created by BZ2 and put in the bindata folder.
When it is created it checks the geometryscale setting in the ODF.
If you try to just add said tag to your mini scout and put the normal scout stuff in, that is a BAD idea, it wont work.
You must get the ivscout00.xsi from the bz2 xsi pack, rename it something like ivmscout00.xsi and mabye change some of the hardpoints around.
The normal scout 3Ds for animation can be used since scale is the only change, and animation 3Ds are not actuly shown inplace of the normal 3D, but have their animation data read and applied to said model in game.
Got it? :-p