wiring under cabinet lighting to combination switch

i'm installing under cabinet lighting. in order to provide electic i've converted an ordinary to 2 outlet to a combination switch. the house was built in last 10 years so wiring seems up to standard hot (black) line and neutral (white) line and a hot and neutral load. in addition there is ground wire. the outlet is the second in line of 4. all the above are connected on the side. ive dropped the wiring for the lighting in and connected them in the backwire area of outlet. in additional the combination outlet/switch is a gfci. the lights light i have power to outlet and the light on gfci lights indicating that wiring is correct for gfci. problem switch doesn't control light. no way to turn light off where did i go wrong???????? help please