I think the asteroid field is locked to give only industial boost, as far as i succeded to see. In my Alex's Mod V3.0 they are a little boosted in a sphere to give exact industrial points at exact distance, which generally boosts them a lot. That is in conjunction with other kind of "chinese" industrial reboost, and all this works perfect for bulping industrial power for econimic price. For pitties sake i have forgotten how i have done it but if you look trough the files, you probably will see how happens

Kind regards:

1Alex3