2) it's an option on the General Tab of the form properties.
"Include <form> tag" or something like that.
3) If Auto-inc is on, and auto-inc is being done, then the form may be in Change mode.
Check to see if it goes out through PostUpdate instead?
(From your description, it should _not_ pre-auto-inc, which is something you can control on the Advanced tab of the form options.)