After a little over a year after I put in my form one I finaly heard back from batf about my form 1.
It had a bunch of minor things that needed to be chanced. I called and they where very nice, the woman that handle my form 1 even send me an email with what needed to be changed. Before the letter got to me. I made corrections and sent a pdf with them to her to look over before I sent back in. She was very helpful and said I should have my stamp with in 30 days after they get correction are sent back.  
I can't wait for it to get here. I have lot of projectiles I want to try out.

I'd be interested in seeing what loads you come up with.  I registered my 37mm last year but haven't gotten around to load development yet.

I have several in mind to try in it but will not put any together until I get the stamp.
I am going to order a 12 ga shotshell adaptor for starters.
Right now I have made some 12 ga shotshells with 7.5 and 9 shot using trailboss powder. Our of my single shot  shotgun recoil is hardly anything and at 30 yards I am smoking clay targets sitting on a  back stop.  I am going to work up some more shot loads with larger shot and maybe some buckshot.

What is still in concept is filling proper size tube with hotmelt glue for a solid 37 mm "bullet"
Make some wads using cardboard tubes for a 37mm shot shell
Use rubber balls for non leathel use for pest using above homemade wad.
Use cardboard tube for light primer powered projectiles for backyard fun.

This is just a few that I am thinking of making.

I am really hoping the light 12 ga works as well out of the 37 mm as it did with the shotgun. If it does I want to mount it to my ar15 in 22 long rifle so I can use for small game hunting. 22 lr on top large shotshell under.