Hi, when I take my gliders out to play I sometimes put them on a shelf because i'm training them to jump to me, when they get out of their pouch they tend to drag their back legs around a bit but the shelf is quite smooth and they don't seem to have any dificulty jumping or climbing. The only time I have seen them drag their legs is when they are on the type of material that the shelf is made out of (it's kind of like a laminated wood) and they are active and eat well.
I'm pretty sure it's just that the material is a bit slippery but i'm still fairly new to owning gliders and I want to make sure that they are ok.