This message has nothing to do with the osbot client as far as I know, it literally means you tried to login too many times to a certain account.
Maybe that the jagex launcher skips that check since it's linked
I have no idea about that, 'm not sure how the inner mechanics of the walkingevent works, you can tweak it some with other option you can add like minimapdistance, ... maybe that helps for you?
Very strange, no matter what task you do they all use the same code, Can you grab a screenshot of the exact issue because when i tried running it was fine
EDIT:
Doesn't that have to do with the fact you are doing multiple tasks in a row? and at lvl 15 you do something new?
There are the same for everyone, you just need to do some magic with bit 2, 3 and 4 of config 1666
Been using that for a few years now and never heard about an anomaly