On the finger print cards, you must put the reason, i.e. NFA TRANSFER. This is what I have done on all mine. 6 so far.
The photo must be a 2" x 2" just like a passport photo. Shoulders up, no sunglasses, hats or other things that hide your face.
Last, do not glue it, but either double sided tape or roll some clear scotch tape on the back of the photo and attach it to the form. Glue may soak through the form and make a big mess of everything.
Last thing that I do, I make 3 copies of all forms. So when they say they lost a copy or you only sent in 1 copy, you have the other ready to ship out. Doesn't cost any more to do that. Plus I have a copy at the house if I need to check anything.