Well, it's two very different "bugs" here.
For the claw, it's just missing (placeholder) art. The animation is in the iqm file, and it's probably easy for one of the artists here to fix this by taking the sword2 animation. Once that's fixed in master, you could just put the new iqm file in the right place of your user content (home/data/weapons/claw/claw.iqm).
The flickering you observe is maybe a GPU driver issue. Actually, the issue I linked above is something completely different from your description