If the cable is twisting too much, you can try this: With just the needle (no stitches on it) turn on the hot water at the sink. Hold the needle out straight and run the cable back and forth under the hot water several times. Keep holding the cable out straight for several minutes until it cools off. Hopefully it won't be so twisty.
For joining try this - cast on your 72 stitches. Don't join in a circle yet, just turn and work the first row as for flat knitting. Now join them into a circle. Since you've got a row done, it should be way easier to make sure you're not twisting stitches. You can use the tail of the cast on to sew the little opening shut.