LATE RWY CHANGE ON RIIVR STAR TO LAX RESULTS IN LOSS OF HABSO INTERSECTION WHILE PROGRAMMING THE CHANGE.

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WE WERE DESCENDING ON THE RIIVR ONE ARR TO LAX AND HAD PLANNED FOR RWY 25L. JUST PRIOR TO RUSTT; CTLRS GAVE US RWY 24R. IN THE REPROGRAMMING OF THE FMC WAYPOINT; HABSO WAS DROPPED OUT AND ACFT STARTED A RIGHT TURN TO RIIVR. I FELT THE RIGHT TURN WAS PREMATURE AND SELECTED HDG SEL TO INITIATE TURN BACK TO THE LEFT. WHEN I FINALLY GOT THE FMC CORRECTLY PROGRAMMED FOR THE ARR AND RWY 24R WE WERE NOW LEFT OF COURSE AND HIGH. THE CTLR NOTICED OUR OFF COURSE FLT AND ALSO NOTICED OUR CORRECTING TO THE RIGHT; THE CTLR ALSO AT THIS TIME GAVE US AN UNRESTRICTED DESCENT TO 10000 FT. ONCE WE WERE PAST RIIVR AND HDG TO JAXEV; WE REGAINED THE CORRECT COURSE BUT WERE STILL WORKING OFF THE EXCESSIVE ALT. BY DECOR WE WERE BACK ON BOTH COURSE AND ALT. THE REMAINDER OF THE APCH AND LNDG WERE UNEVENTFUL. AT NO TIME DID THE CTLR ISSUE ANY TFC WARNINGS/CONFLICTS NOR DID THE TCAS ISSUE ANY WARNINGS. UPON REVIEW I REALIZED THAT I HAD INCORRECTLY REPROGRAMMED THE FMC TO ACCOMMODATE THE RWY CHANGE; THEREBY CAUSING LATERAL AND VERT DEVIATIONS. FUTURE PLANNING TO INCLUDE SUCH RWY CHANGES WILL BE ADDED TO MY BRIEFING TOOLBOX TO HELP MAINTAIN SITUATIONAL AWARENESS.