My daughters using a Libra with a treeless pad on her fell ( due to her becoming too wide for her h&c)but although everything else is great it does tend to move about a little. I am clueless when it comes to treeless saddles, the pony is very flat, round, no withers, is there anything I can do to improve this or is it something we have to live with cause she's so round ATM. Any advice appreciated.x