I just checked DeLorme website for minimum system requirements of Street Atlas, but there is no specific mention of 64 bit Vista - it only states the supported operating systems include Microsoft® Windows® Vista™ Home Basic/Home Premium/Ultimate/Business, etc, etc, etc.
My guess (only a guess) is that this issue is not related to compatibility problem, but perhaps it may be related to a missing file(or files). But, unfortunately, since you are not the legal licensed owner of the product, DeLorme will not help you, and people here at the forum generally don't look favorably at using and/or testing of unlicensed software.