Yes, if you take all your IDCs at once, and you have sufficient excess IDCs, you do have an AMT adjustment. And I agree, limited partners don't qualify for the working interest exception. It's unusual to see an O&G partnership that starts you off as a limited partner; I'm guessing the "you get a big tax deduction in exchange for your cash" selling point isn't the selling point these days.

If he has both basis and at-risk, there shouldn't be any disallowed amount. Lacerte is generating a basis schedule (either as a statement or a worksheet), and it shows sufficient basis? The 6198 has a positive amount on Line 20?

The last time I had a weird basis limitation I wasn't expecting, I had a deduction entered as a negative amount, rather than a positive, and it made Lacerte unhappy in really strange ways.