Sanwu Pocket: How to fix rattling/loose rear clickly switch

I just received my first-ever Sanwu laser: a 500mW 445nm Pocket. It's AWESOME and I love it.

I just wondered if there's a way to fix two small things:

1. First, the rear clickly bottom is loose and rattles (it works perfectly, but if I shake it, it rattles. There's obviously no spring pressure again the button itself).

2. I would like to increase the resistance of the focusing head. Anyone know of an easy way to do this?

Thanks so much.