If AutoDesk says it's incompatible, the argument ends there.
If you proceed with the using XP Home, and have a problem, the first words out of the support tech's mouth after "It's not Supported" will be "Upgrade to <something that's supported>." No further action is warranted on their part, even with paid support, since you're using a non-supported config.
I can't see any reason WHY XP home would be incompatible, unless it's related to a networking/domain issue.
Selling unsupported solutions usually proves out to be a bad thing. If it ever ends up in court, your A$$ is hanging WAY out there.
FWIW / .02
Scott