The 1 and 11 cards are special...but are colored. So if someone leads a trick with, lets say blue, and I have a blue 1 or 11, I have to play it to follow suit if I have no other blue cards to choose from correct? Or of course play it freely to follow suit when I feel it helps me.
Yes you'll have to follow suit with the 1 and 11. So you may be forced to give up a 1 Knight that scores you 3 pts if you hang on to it until the last trick (IIRC).
If I have no red to follow suit can I throw a 1 or 11 of blue to dump?
Yes, you can dump any cards when you run out of the leading suit.
The other special cards...Can some only be played (unless stated on the cards), when you can't follow suit?
I don't have the cards with me now but I think the beige special cards can be played even when you can follow suit. Perhaps someone else can confirm/ dispute this. I remember there are restrictions to lead with a few beige cards though.
This is a very fun and highly replayable trick-taking game. Even players in my group who have not played trick-taking games got hooked!
Hope you have a blast with it like I did.