On the windows, you will need to pull the windows out by removing all of the inside window trim ring screws and pull the windows out. Clean off the putty or foam seal and use butyl tape around the outside flange and re-install the windows after wall repairs have been made. Trim off any excess butyl that oozes out for a couple of days and then seal parameter with a silicone sealant. For the air conditioner, you will need to remove the inside ceiling assembly and lift off the roof assembly and replace the roof gasket. Re-install the roof assembly and evenly tighten the mounting bolt to 65 inch pounds of torque. The most common sealant for roof seams around fixtures is a self leveling lap sealant. A common brand is made by Dicor and can be purchased from RV supply sources. All that is needed is to clean old sealant of dirt and greases and recover with new sealant. Good luck and keep us posted of your progress.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7