We had one of those, and I do not remember any adjustments. It was a torsion spring that ran the entire length of the slide out. That spring broke while traveling once and I was fortunate enough to see the cover flapping in the slip stream. I stopped, got the ladder and was able to roll it back as we reclosed the slide out. Not difficult to change,but get the directions on-line from Carefree of Colorado. If yours is weak, I suspect your option is to change it out. Took about an hour. Be cautious, as you will need to preload it prior to closing. Seems like I had to pop rivet it together once the preload was set.
2007 Dutch Star 4320
2010 Mazda Miata 6 speed