In my experience vista and 7 doesn't like you to do ANYTHING without it needing a quick "repair", but installing an MD definitely shouldn't cause any problems.
I assume you had to change boot orders, maybe enabled onboard ROM etc before you could use the laptop as an MD? That might be enough for windoze to go willy tits, but if you put everything back the way it was before you re-boot vista, it shouldn't have caused a problem.
Cheers,
Matt.