For items that only walker picks up, there is a patch on Hint's webpage I think. May be if you put in walker "not pick up" for "all the same" and then add every item that you want to pick up, the bot will not pick up the "ban-item".
Use DISABLE option if you are facing a GM.
For gmlist, set the refresh time to 9999.
For buff that are made every 20min, I'm not sure if admin can really control that. In any case, just put 19,5 min or 20,2 min.
I don't know if walker really attacks a gm when he is as a mob ? Can someone confirm this ?
Just don't move your bot and it will look like you are loading. And I don't think that an admin would ban someone for this. I play in windows mode with low resolution and the game does load up very fast.