PMDG 737 FMC Error Message

Okay, while still being a tenderfoot at all this FMC stuff, I'm most likely doing something completely wrong, but here's my deal:
After reading the PMDG 737 FMC manual, I figured I would go ahead and load up a flight and see if I could actually program the darn thing. I use the "flight planner" and plan a flight from Sacramento to San Diego, and note all the waypoints and airways that would be used.
As needed by the FMC, I enter all the waypoints to the RTE pages, (e.g. Direct to LIM from KSMF, to AVE via J189, to DERBB via J7) etc.
Once I pass all the waypoint entry pages, and reach the SID selection page, I choose a SID that goes along with my taxi clearance from ATC to a runway. However, once I choose a SID, then I get a message in the scratchpad reading:
DISCO inserted after LIAMM
Along with this, the first three waypoints on the now MOD RTE pages show "Route discontinuity" across them.
What am I doing wrong?
-HF
After reading the PMDG 737 FMC manual, I figured I would go ahead and load up a flight and see if I could actually program the darn thing. I use the "flight planner" and plan a flight from Sacramento to San Diego, and note all the waypoints and airways that would be used.
As needed by the FMC, I enter all the waypoints to the RTE pages, (e.g. Direct to LIM from KSMF, to AVE via J189, to DERBB via J7) etc.
Once I pass all the waypoint entry pages, and reach the SID selection page, I choose a SID that goes along with my taxi clearance from ATC to a runway. However, once I choose a SID, then I get a message in the scratchpad reading:
DISCO inserted after LIAMM
Along with this, the first three waypoints on the now MOD RTE pages show "Route discontinuity" across them.
What am I doing wrong?
-HF