I bought a new house and the previous occupant kindly left her compost
tumbler. I've been filling it & turning it daily for a couple of
months & things seem to be happening... but I've got a couple of
queries:

1. There are quite a few smallish twigs & stalks which, unlike
everything else, aren't rotting down. I may have put in a few too many
- but is there anything that I should be doing to help them rot down?
(Or will I just have to wait or live with it).

2. There aren't any worms in it (possibly as it's a compost tumbler on
a stand & raised off the ground by about 6"). Does this matter?
Should I think about buying some?

Thanks,

Michael