MD80 CREW MISSES CROSSING RESTR ON CIVET INTO LAX WHILE LOADING RWY CHANGE IN FMS.

Narrative

WE WERE CLRED TO DSND VIA CIVET 5 ARR. AROUND GRAMM OR RUSTT INTXN WE WERE GIVEN RWY 24R. WE WERE SET UP FOR RWY 25R. I WAS THE PF. I ASKED THE CAPT TO MAKE THE CHANGE IN THE FMS FOR ME. HE SELECTED THE CHANGE. I HAVE HAD PROBS IN THE PAST WITH LAST MIN CHANGES WHILE ON THIS ARR. JUST TO ENSURE THAT THE LOAD CHANGED I ASKED HIM TO VERIFY THAT IT LOADED OK BY CHKING THAT THE CAMDI INTXN WAS SHOWING IN THE LEGS PAGE UP-LINE. TO GET THERE; HE HAD TO SELECT PAGE TWO ON THE LEGS PAGE. I NOTICED PASSING I THINK IT WAS THE RUSTT INTXN AND THEN LOOKED TO THE LEGS PAGE TO SEE WHAT ALT WAS NEXT. NOT SEEING THAT THE LEGS PAGE WAS STILL IN PAGE TWO I SAW AN ALT (I THINK 12000 FT) TO BE SET FOR THE NEXT STEP-DOWN; WHICH I HAD HIM SET IN. I CONTINUED IN IAS 250 FPM DSCNT; BUT SUBSEQUENTLY NOTICED THAT THINGS WEREN'T ADDING UP AND FIGURED OUT THAT WE WENT BELOW THE CIVET BRACKET ALT OF BETWEEN 14000 AND 15000 FT. I LEVELED OFF IMMEDIATELY AND GOT REORIENTED TO THE PROPER ALT AND GOT BACK ON THE PROFILE DSCNT. APCH NEVER SAID ANYTHING; AND WE DID NOT COME CLOSE TO ANY OTHER ACFT. THE LATE CHANGE; COUPLED WITH MISSING PAGE TWO BEING SHOWN ON THE LEGS PAGE GOT ME OFF PROFILE. THE CAPT WAS HEADS DOWN; BUSY DOING SOMETHING WHEN THIS OCCURRED. I HAD THE CHART OUT; BUT RELIED ON THE LEGS PAGE. IN THE FUTURE I'LL TRY TO HAVE BOTH PLTS CONFIRM; AS WE ARE SUPPOSED TO; CONFIRM ALT CHANGES PER THE PROFILE.