IP Rights Question

We're in the process of licensing the rights to some intellectual property (hereforth IP) in an effort to reduce our creative development costs (we are a garage developer, so money is always an issue). We're looking at a 5 year deal on this IP (with the possibility of renew option for additional 5 years provided certain goals were met), only for electronic entertainment products, and restricted in such a way as we don't impact or alter in any way the way the IP holders' IP is perceived.

Something similar to how FASA lets various publishers make MechWarrior games, but they cannot alter in any way the background, plots, characters, or stories without FASA's express go ahead.

Because of this licensing of IP are we going to have some major problems with using the V12 engine if we decided to do so, or could something like this work out within the V12's licensing scheme. Or is there a way to make allowances for this type of sub-licensed IP to work?

I can see a possible worst case scenario type problem arising if we're required to hand over IP that doesn't belong to us, resulting in the corruption of the original IP holders IP. And basically, we'd like to avoid causing anyone any grief (we just want to make this game).