Some of the recent problems with the borg selecting diggers and other strange equipment choices related to him being encumbered and incorrectly trying to maintain a high strength bonus. I used an incorrect if-else formula. That is now corrected and he should not be making that same mistake. If he is keeping his odd equipment choice, he might still be wanting to keep his strength up, but it is probably a proper choice. Look to see if the borg is encumbered (over the weight limit). If it is not over the weight-limit, then start to question the selection.
Generally, the borg will not attempt to open a door if a monster is adjacent to him. A borg got stuck between a monster and a closed door and was too afraid to attack the monster and he was forbidden from trying the door. The borg just sat there. I added a fear check to allow the borg to attempt doors, even if a monster is adjacent, if he had the ‘fear’ flag.
I did see the borg with one digger equipped and about 10 weapons + 1 more digger in his pack. It turned out that he was quite a bit over weight (from lugging around 10+ weapons) and the digger had a ridiculous +8 to strength that he tried to take advantage of. He then replaced the digger correctly when he returned to town and sold of the excess weapons. (While he was still in the dungeon he seemed to switch between the two diggers when he was digging…)
Rubble still freaks him out.