Oh no Not Scraggy again - !!!

Yup! I am almost ashamed of posting more on the same problem, but I really need to get this right...

Ok I started simple, made a room - made a hole for door and window and tried to use Split Poly ... Not Extrude face (Straight off)
The problem starts when I try to draw my 'edge' (split poly) It obscures the hole cut by the boolean...!
This is ok on the 1st split, but not for subsequent ones? so does this mean I :-

a./ (Haven't tried yet, but it may work?) - Put all the splits in 1st... then cut the 'Hole'

b./ This seems a bit intensive ... make the frame from new poly's?

So I didn't make another useless post I checked and deleting history does not make a diff, and tried with 1 cube (not my room)
Below :-