I warp from front to back. There is always a little twisting, but I can usually straighten things out when I tie on in the back. I also use lease sticks to provide more tension between the back beam and the heddles. The sticks help straighten out any twists in the warp. Warping can be frustrating. I think the most important thing is to have good, even tension. Good luck!
Me, too. All that twist works to the front of the loom when winding onto the back beam and I comb it out as I go. I straighten out the very last of it when I tie onto the front rod.