Hi Mike,
There should be no "Strange behaviour" comming from an export out of MoI... Sounds like a unit change somewhere in the process. Can you post this simple example file so we can look. I have a few cad packages i could check your file with.. Most likely there is someone here with your exact package that you are working with too. Whats the other CAD package that you are going to? Be sure you know the units it is working in.