I can't help with the perforated headlining, but my tourer headlining is sagging.
I glued it using the correct adhesive (in my view) and a vinyl wrap squeegee to smooth down. Brilliant result, but, unfortunately it caused other sections of the lining to sag! If you go down the glue route, ensure you mask off the bits you don't want to glue as it splatters quite a bit.
Glue:
https://www.ebay.co.uk/itm/Trimfix-A...53.m2749.l2649
I've decided to use pins for the time being until I can afford the bill at a trimmer.
Good post here
https://the75andztclub.co.uk/forum/s...rer+headlining
Good luck!
Geoff