Michael J Fox was the star.

Crispin Glover (George) appeared once as a friend of Alex's.

Cristen Kauffman (Lorraine's friend Betty, the blonde one) appeared in an episode.

I would guess, as a friend of Mallory's? I always thought it would've been neat if Christopher Lloyd had a guest spot in the series.

It was either a friend of Mallory's or a love interest of Alex.

I should maybe check IMDB a little later today.

She played Cindy Sullivan in the 1982 episode "Oops"

I'll have to watch that episode today. I guess it's the girl who got pregnant, and was afraid to tell her mother.

Elsa Raven who played the Clock Tower Lady played Mildred Atkins in the 1986 episode "Checkmate"

I'll have to be on a look-out for that! :)

Did Christen Kauffman play the pregnant girl?

I think she did. I'll have to double check, though.

It's kind of weird that Greg only appeared in A, My Name Is Alex. He was supposed to be a good friend of Alex.

That's the one problem I have with Family Ties, is the lack of continuity. I'm not sure whether to include Greg in my FT ficverse, or not. I think they brought in a character to be killed out, because the only friend of Alex's who really appears regularly is Skippy. The others we only see once or a few times, and then we never see them again.

Crispin Glover's character only appeared once.

Yeah, in Birthday Boy. I know there was also a Doug and a Neil in the episode where Alex drags Jennifer along to a poker game, but I'm not sure if they're supposed to be the same people.