Can't speak to the slide awning (Except to say that story may sway me away from installing one...)
If the water in the windows was from condensation, you should consider adding a vent cover and keeping the vent open to let out the moisture. Again, if it was condensation, there are weep holes at the bottom of the window designed to let that water out. If you can open another window or vent, it helps remove some of the moisture. Some of mine don't work very well, but we've only had a condensation problem once, so I don't worry too much about them.
If it's not condensation, then you have the unenviable task of finding and fixing a leak. I don't get any water in my slide windows except for condensation when it's cold and wet outside and I'm cooped up inside running the heat.
2014 Jay Flight 28 BHBE
2015 RAM 2500 6.4L HEMI, Tradesman 4x4, 3.73
Blue Ox SwayPro (BXW 1503)
Upgraded from an REI internal frame backpack and a Eureka 1/2 dome tent!