In that image the white is the wood trim and the dark brown on the inside is the Anderson replacement casement window. The windows were smaller than the originals so they were shimmed and then the space covered with the white wood.
I dont think water can get in there because the fit is so good...
I have pretty good seams on windows, I am wondering if they should have been caulked. If so i will do before painting. I live in lower NY state.
I know some areas i need to caulk but was wondering if the joints where i have the red arrows should be caulked?
Thanks~