Yay! I'm so glad it went well and everything worked out =] Just a few tips for next time you perform for a crowd like this (now that I've seen the video I can give you better input for next time)
One thing, slow down. I have the same problem so I know that it's hard, but when you work with special needs individuals you have to let everything sink in so they can process it.
Also special needs people, for the most part, LOVE to be part of the magic. Occasionally you'll get someone who isn't comfortable with helping you out, but whenever you get the chance to have someone up on stage with you, do it! Example, when you gave the coin to the spec and it vanishes, next time have them come up to the front where everyone can see, and do the vanish. I know it doesn't sound like a HUGE difference than what you did, but it does help a lot.
Great job on the interaction when you pulled out the two black jacks. Like kids shows, when working with special needs, a good rule to have is the rule of three. You asked them if they wanted the easy way or the hard way, then you asked again. If you had added one more saying something like "Are you SURE you want the hard way?" you'll see that the audience is more involved with the effect.
Again as I mentioned before, when you have someone help you out, bring them on stage with you and have them face the audience. It makes the audience as a whole feel more involved. Another reason is without doing this, a lot of your audience can see. When you did the sandwich effect you were really only performing for the spectator and the people next to him. You have an entire audience trying to see, so make sure that they can. You did that for the second phase, which was perfect, just remember that when you bring someone on stage to clap for them so everyone else does as well. This will make them less nervous when they help you.
When you transition from one effect to another, give them time to react. When you finished that firs phase of your sandwich effect you kinda jumped into the second phase before they had a moment to process what was going on.
Don't forget that when you finish with a spec and return them to their sleep to clap for them as well, so they feel appreciated.
If you plan on doing a gig like this again, invest in some good kids show effects. I know when we were PMing that you said you didn't have a lot, which is why you did mainly card magic. Magic for special needs people is just like a kids show, so thats why you should focus on kids show material. Also I suggest you check out Seriously Silly by David Kaye. On the DVD he goes over a lot of theory that can be applied to a situation just like this one.
Overall you looked like you had a good time and so did they, and thats the important thing. Great job, I know performing for the special needs can be tough, but you did great. I have around three gigs at the end of the month for special needs adults, I'll send ya a PM when I post them so you can see what I mean.
Again great job! =]