i have problem with attaching some curves in a same level so i could orient them together

hi. i have a model I've created recently an in order to fabricate it i need too divide it in different layers. i have divided it and in some levels in z direction i have two or more curve created. my first problem is that i can not attach these curves in a same level so I'm unable to orient them with the right label.

i have some additional curves within these main curves which should be laser cut and create some holes for placing the columns.

the main problem is that i cannot orient all of the curves which are in a same layer or level to label them and laser cut them. i find out the actual problem is because of my trees but i couldn't fix them.the problem with this orientation is that the holes are not in a same label with outer curves.

I'll attach my ghx file. thank you guys.