Vista - (Sigh) Compatibility problems... Again

I don't get this. OK, Office is working fine, the UI is... new, getting used
to it, some details about the OS I appreciate a *lot* (aka UAP, better
networking - at least in the UI, I have to reboot twice upon installing
_any_ program, wireless networking comes *down* when I install anything that
requires a restart (grumble) but hey, it's all beta, right?) but...
Microsoft's own games (aka freelancer, rise of nations) will not run!
Freelancer crashes to the desktop, and rise of nations has trouble loading
an XML file. One would think that legacy compatibility should have been
nailed at this stage (although these games aren't even old, they were
developed for XP natively!) Plus, Compatibility mode does not solve these
issues (oh yes I have tried). Any thoughts? Are these known issues?