I have tried to remove a wooden bath panel (by pulling) without success; I cannot see the mounting, so have no idea how it is fixed. Is there a standard method of fixing (that I am obviously unaware of), or should I just use brute force?
normally they are screwed at the corners. It is possible tho that yours may be glued to the supporting wooden frame that runs just under the lip of the bath - although this would be stupid for later access.
Also, I lived in a house once, where the panel was cut so tightly/precise that it actually just held itself in place with the rim of the bath - try pulling the bottom towards you only if this is the case.
Alternatively check that there are no tiles from the walls holding it in or the skirting board.