Ooey gooey messy magical Duoderm

So I've got a pressure sore. My occupational therapist had made some changes to my chair a few months back. One of them was to put a board under my Roho cushion. Since then I keep getting pressure sores on my coccyx. I've removed the board as a result, and hope this doesn't cause more problems with my back/shoulder/neck pain as it puts me a bit lower in the new hard back I have on my chair. I've always had foldable backs. But my toushie skin must be looked after too. So I'm using Duoderm. It's wonderful in the sense that nothing I've ever tried has ever worked as wonderful as it. It's almost magical that way. However, Duoderm's downfall is that it's messy. As it interacts with the pressure sore, it gets gooey and leaks. And the odour is foul. The rub is that Duoderm only seems to work optimally if you leave it on for about 3 days before changing it. The goo is needed in the healing process. So I keep adding tape around the leakage parts and wash around it. However, taking showers and getting it wet seems to impede the effectiveness of the tape and makes it easier for the goo to seep out. It's a huge nuisance, especially if you work and have to interact around people, wondering if it's oozing. Does anyone else have this problem? Are there any Duoderm secrets that people have for making it work best?