How do the bits fit into the holster?

Slip the bit clips vertically under the elastic strap. The magnetic picker goes in the spine (middle) of the holster.

Not sure what the problem is. I had to "invert" (think turning a sock inside-out) the pockets so the bits would point up instead of down; this way they won't have any chance to fall out of the elastic retainers while wearing the holster on my belt. If you are having a problem with the zipper, don't force it; try rubbing a little candle wax on the teeth and work the closure a few times with the holster empty.

The bits sit down into a little square tube and then ride tubes slide down into elastic pockets.