I used the KSB diamond clear on the nose and some film repair areas on my YakYak bipe, applied with the foam brush (that they included in the trim kit $19.50). The humidity was in the mid 60% and temp around 72F. It worked just like Mike G said it would, leveled no brush marks. I did not thin, took about two days to cure out hard. The test will be in the flying to see how it holds up to 7% fuel. You might take a heat gun and just warm the surface a bit to kick it off.
Best, Dennis