Replying to Front swap?

Ive been working on locking onto tubes/rails and have been able to pop and 270 off somewhat consistently. I'm now trying to front swap with a similar idea of putting pressure on my skis either side of the the rail to rotate my skis for me, but ive found when I try and rotate and pop i end up moving off the rail and I cant keep my momentum going down to let me land back on the rail.

My questions are, is there something I can do by putting more pressure on either my front or back ski to keep my movement downhill? and, Is there a different way I should be approaching the front swap, either like a flatground 180 or something else?
thanks