RE: Getting Ultracote to stay down?
Switch to SolarTex. It is a prepainted fabric, and even with a clearcoat (to prevent fuel/exhaust stains) it will breath, so it will not wrinkle.
Also, as mentioned above, make sure the surface is ABSOLUTELY clean and free of dust (after vaccuuming use a tack cloth ) so the covering adheres to the wood, not the dust.