I did have to zip tie the fender well liner back. You just poke a hole in the liner and use a zip tie to hold it back. It just took a couple of minutes on each side.
I have been using a RetraxPro for about 6 months and it functions extremely well. While it is not the most flush cover I have seen, it is very easy to use and does not leak. I can't comment on the install as it was on the truck when I bought it.