We have a 2012 Grey Wolf that we bought used a few years ago. Ive noticed the rubber roof has what I'd call "spider cracks" all over it. Some places are worse than others. I suspect someone might have...
My 2007 Travel Star looked just like this. I used Dicor product and was very satisfied with the results. Follow this link and you'll see the pics I posted. https://forums.goodsamclub.com/index.cfm/fuseaction/thread/tid/29286956.cfm
You can also email Dicor with questions and they respond within a day.