Curtain wall grid disappears

[Alex Page]

This is odd....noticed my curtain grid lines disappeared on some of my walls - they are still there but not visually.
recreated the wall but the same problem...but if I copy/ move the wall away from the rest, the grid lines show up again!
Refer image and note Ive shown the copied wall at the front (which looks fine)

Note:
I havent added/removed segments of the horizontal grid line
The panels are a basic type of wall and are all the same
Using 8.0

Suggestions?

[E-Key]

Looking your drawing it seems the problem is in joint with garage door wall. Try to play with it or send the part of your drawing

[Alex Page]

Thanks...but worked out the problem was probably due to the proect being upgraded from previous release....redrew everything and everything worked fine