Looking good so far. As the windows are attached with PVA, be very careful when masking, particularly when removing the masks after painting. Before applying any masking tape, run it between your finger and thumb, pinching slightly, to remove some of the tack, and fit it lightly in place. This should minimise the possibility of the windows pulling out when the tape is removed.
For future reference, if at all possible, fit windows after painting, if they don't need to be blended in, and can be fitted from the outside, and 'stuff' the apertures with damp tissue or crumpled kitchen foil. They can then be fitted after painting the model, by applying a few small spots of PVA (white glue) to hold the transparent part, then sealing the entire window in place by running a thin bead around the periphery, applied from the tip of a cocktail stick.