Ok, I got it... I will try to make it in three parts, I don't have profinish but will try glueing some fg in the back before cutting.
Another thing I would like to try is to put the twill 45 degree with the recess because it seems it coluld distort less.
I will tell you the results..
Yesterday I demoulded the part made in one piece with twill, but the distortion was even more then with the plain carbon..

As you can see I also had a problem of stiching to the mould, so I had to breack the part to pull it out...
The resin has attached to the clear in the mould.... I had cleared it since I had to make some sanding in the mould and it seemed a good idea...
I think next time I will not clear the moulds again! Or at least put also pva on the easylease (even if it seems a nonsense)