One tip when I painted our kitchen was to put old jam jars, bottles or similar on the floor and lay your doors flat on these when you have painted them, prevents any runs or 'blobs' of paint accumulating.
We also used the small gloss sponge rollers rather than brushes this gave a lovely even finish, though is probably not as 'glossy' a finish that brushes give you. We were after more of a country kitchen feel, so this worked better for us.
Just take your time and a few days later you will have a brand new kitchen for a couple of hundred euro, good luck