Taxi lines not showing up

I've successfully added an apron to a default airport that only had a single runway(no apron). I've added in some GA parking spots, taxi lines that connect to the runway and apron and also a runway hold short point, but none show up in FS9.

Strange because I've had no problem adding them to another airport. \

i'm wondering if its because there wasnt any apron previously so its conflicting with the apron I added?

Any help greatly appreciated.