If it'* leaking..you'll be burning coolant.
Did you clean the gasket surfaces well before reinstalling the new gasket?
On the RTV, I used to use it on everything that looked like it could use a dab. Over the years and working with my mechanic buddy I learned that adding RTV to anything is adding another cleaning from he ll in the future. The factory assembled many gaskets dry and they work 100% for years. You can do the same unless the directions specifically call for RTV. To make your job cheaper and easier.. don't use RTV if it didn't exist there to begin with.