Glider Skin - Bug or i'm noob ?
You can change Glider skins in the Hero Panel under the Glider Skins option (very bottom choice). Just click the one you want that character to use.
Good luck.
You can choose what glider skin to use through the Hero panel, Equipment tab > Gilders. There you will see which one you have as active and choose another one (if you have any).
lol and Inculpatus just beaten me :P