I'm on the plan, and keep meaning to post a big update, but haven't had the time.
For the BHA i'm using Neutrogena Clear Pore Treatment, which is 2% salicylic acid, and is like a clear gel. It's meant to be left on overnite, but works just fine for the program.
For AHA, I'm using Alpha Hydrox Oil Free Formula, also a gel like consistency, with 10% glycolic acid. This stuff is great, doesn't irritate my skin, and is only about $10. I did have to get used to it- it burned at first, and sometimes I'd have to take a day off from it, but otherwise no problems.
For BP, I'm using Neutrogena On the Spot Acne Treatment, a standard BP white creme, with 2.5% BP.
I bought one of those reusable ice packs, made for use on joints and stuff, and that works fine, so i would think if your face pack is freezable, and reusable, it should work out great. If it is freezable, and reusable, let me know, and post the brand, so I can get one too!