For example, I ran into these bugs in a single run in 0.2.2 download version.
1. Golems don't trigger events.
2. Pickaxe doesn't unlock. Its unlock condition doesn't make sense -- instead of reaching rock depth, it requires acquiring rock. As a side effect, golems will never unlock pickaxe.
3. Golems cannot remove snow.
4. Golems eventually stopped dealing damage to blocks (at 3xx white blocks metalic-heart). Depth remain same, and statistics doesn't change. Statistics occasionally update, possibly due to the tiny chance super crit (golem damage rate < 1% player damage rate).
5. Golems statistics is probably too low.
23 is old bugs since 0.2.
1 is one of the reason that 0.2 golems are so underwhelming (and pickaxe bug).
There was some old bug of blocks keep being unknown on acquiring, which might get fixed in current version.