Maybe it's just me, but I simply hate the smell of various repellent candles or other burning repellents. On some occasions I've had them burning outside the cabin door, but it seems the smell finds its way in. And as others have stated, applying chemicals on your tent without testing first on actual tent fabric is a bad idea.

The netting in my old tent door stops pretty much all flying insects we have around, no chemicals required. A few will get in with me, but it's easy enough to find and kill them in the small closed space. I doubt the netting would stop ticks, but my understanding is ticks don't actively close in on you from distance like mosquitoes do. I actually prefer sleeping in a tent if the area has lots of mosquitoes. Sitting around the campfire, that's another story.

--J