Stupid window question.

OK, don't laugh, but I have a window question.
I bought two door windows and a large front window from Lil Bear a couple of years ago. They're standard, operating, anodized black camper windows and they came with inside rings.
My question is this: there are no holes for mounting screws anywhere on these windows? However, the rings have screw holes. Am I assuming correctly when I think that you're supposed to drill into the flat, inside, of the windows and run a sheet metal screw through the ring and into the window?
Also, the windows all have a rubber ring gasket inside the outside face that seals to the outside of the camper. Does anyone use additional caulk around the inside of the outer lip, or is the gasket enough for sealing the window when it's pulled in tight by.........see above stupid question.
Any assistance would be greatly appreciated. I'll also except snide remarks and digs . A pox on me for a clumsy lout.
Have a great weekend.
Brian
I bought two door windows and a large front window from Lil Bear a couple of years ago. They're standard, operating, anodized black camper windows and they came with inside rings.
My question is this: there are no holes for mounting screws anywhere on these windows? However, the rings have screw holes. Am I assuming correctly when I think that you're supposed to drill into the flat, inside, of the windows and run a sheet metal screw through the ring and into the window?
Also, the windows all have a rubber ring gasket inside the outside face that seals to the outside of the camper. Does anyone use additional caulk around the inside of the outer lip, or is the gasket enough for sealing the window when it's pulled in tight by.........see above stupid question.
Any assistance would be greatly appreciated. I'll also except snide remarks and digs . A pox on me for a clumsy lout.

Have a great weekend.
Brian