Kay,
What machine hoop and stabilizers do you use for the towels? In the hoop, try holding the center point on each side when you snap into the hoop. I haven't ventured into towel projects yet but hopefully soon.
Hooping:
https://www.youtube.com/watch?v=qjSnEFXCKLE
You can use a little spray baste on the stabilizer too to help hold down the towels. Another way is to fold from center point so you have the four quadrants on the item. Match the center points on stabilizer and towel.
Using sticky:
https://www.youtube.com/watch?v=qjSnEFXCKLE
Sometimes I have to move the design on the machine to get it centered due to hooping. It's a dance for sure to get everything lined up.