Yes, it is feasable to use icf's for basements as well as above grade,.......that's what icf's are used for. Not sure what you mean about laying down sideways, or wall support? Waterproofing is easily accomplished by one of several methods. I don't know about the free panels thing. I think as you do more research as to how icf's work you may find that it's more practical to use icf's vs panels (whatever they are).
Bunt