If you have difficulties to crochet the cord for Romanian Point Lace the problem can be the hook.
As you can see from photos the hook is very thin all along length.These are the original hooks (from Romania) used for RPL. Small number crochet hooks from England or Italy (no 0.75 or 1) are small only at the end.
Try to find hooks similar to these, very thin on all length. Even here, in RPL country, only one factory still produce this kind of hooks.
Have a good day ladies.