For the last week or so I've been running this script on four accounts for 2-4 hours, twice or three times per day. Before that I had a few bans with longer play sessions, but since changing to that, no bans at all. And even with those accounts, they'd usually have met the trade reqs before being banned. I feel like there may be some other variable causing your bans, maybe jagex have flagged your hwid/mac address if you've had a lot of bans?
As a side note, a hotkey or button to toggle the paint would be a nice addition, to see the chat box