I have made some major changes to the backend of the PDAClassic skin and the skin functions. If you have made a PlayerPal skin it may no longer work on version 3.5. I have done this in order to try and make a better skinning experience moving forward and I have banked on the fact that only a small number of you right now have made changes more significant than CSS (which will still work).
If you have done a lot of skinning and this change is a big problem please email email@example.com and I will see what I can do to help. I'm sorry for any inconvenience. Rest assured that as PlayerPal matures the interfaces will stabilise.