Thanks-- the fact that it was in the LTR website and was called "Digital Work Permit" threw me off. It really sounded like I needed that to do digital work. But this makes a lot more sense now since the DWP form didn't make any sense.
What about coming into Thailand with LTR? Do you have to disclose anything about your work? or do they usually just see the LTR visa and not ask any further questions?