Yea... sorry if I my reply sounded umm... confrontational, it was more of a gentle warning since your in the the grey area. From a technical perspective, I do however disagree with:

Fair use does allow me to take that work, cut the church out and move it to the right to break up the alignment of buildings to fit the arbitrary paper size that the publisher needed to work with. That allows me to use the product in my own game. If I do that myself it is perfectly fine.
Fair use generally does not give someone to right to modify anyone else's artistic work with express consent, even cropping for example. Ultimately, it's un-enforcable for you to do it yourself assuming you don't republish your "changes" somewhere but technically, it's far more likely to be a copyright violation rather than not.

However, it's far easier to justify fair use by having someone (or yourself) else re-imaging the work as opposed to modifying the original in any way.