You're missing ..
* Sponsorship Agreement (1344B)Yes, you need to send the
Document Checklist / Sponsor along with your application.
I don't recognize the "Appendix A Checklist." But it wouldn't hurt for you to send that, too.
For your police checks, I suggest you apply for the FBI background check as soon as possible. The absolute minimum they can process it in is about a month. And if you don't specify a deadline, it could take 3 months. So write "DEADLINE: xx/xx/xx" on both the outside of the envelope and on the application, itself. I suggest putting a date of 2-3 weeks from your mailing date. Anything shorter won't matter - they have to have at least 2 weeks, and then you add mailing time and office "shuffle." They're pretty good, though. Here's a link to the FBI's instructions:
http://www.fbi.gov/hq/cjisd/fprequest.htm