Hi miquik,there was a big change in the AI format back around Adobe Illustrator version 10 - with v10 (or v9 maybe it was), the format switched to just basically be a PDF file. MoI though writes the older style AI v8 files.

Some programs will only load the newer PDF style (Inkscape is one), and some will only load the older style and some will load both like Adobe Illustrator itself can load either.

One inexpensive drawing program which can load MoI AI files is Mayura Draw:
http://www.mayura.com/

Also another one which is a free program now is Creature House Expression, you can download it from here:

http://download.microsoft.com/download/a/5/d/a5d625a5-2e3d-4e9c-8608-6de48d7b569f/CreatureHouseExpression3_3.exe

Either of those may be helpful for loading 2D AI files written out from MoI and editing them or exporting them to some other format.

- Michael