I created a Drupal 6 module, and in it I implemented hook_block(). I set up the block to appear in a certain region, and hook_block acted like a blockhead. The block consistently appeared in the Disabled list.

I was working on a new Drupal 6 module, and at least until things became more complex, I was writing it in a top-down manner

It can be very frustrating to do what seems to be everything needed in order to receive USPS shipping quotes in Ubercart.