OK, here is a few bugs I've found.
1. Workbot can't find current beacon if another workbot is staying on it. (After start of algorithm left-bottom workbot will go to upper beacon)
2. Workbot can't find nearest water from lake (I don't know why, because another workbot can do this). From the other hand he can find water from sea.
3. And there are some artefacts on screen sometimes. I think it's when too many elements are on the screen at the same time.