Nacra 4.5 Bias cut Trampoline replacement - can't slide the lateral boltrope

Hi Everyone,

I am trying to replace the bias cut trampoline on a nacra 4.5. The old one was sliding out of the track and was worned out.

The new one must be a little tighter and I can't get it to slide in the tracks .... too tight.
Do you have any idea how to get it to fit ? Should I try to compress the hull ? Or stretch the trampoline fabric ? How would you do it ?

Also It came in without boltropes lines so I am trying to find the correct material for boltrope so that it won't come off the tracks, any recommendations ?

Thanks in advance for your help