When employing a glue-on wood riser, it's possible for it to "pop off" when limbs are bent. Preventing this is relatively easy, but may not be obvious. Slope of transition from top of riser to limb (the fades) needs to extend into the limb itself.
Note that slope of fades extends into thickness of limbs.
As others have mentioned, it also helps if riser is made up of relatively thin pieces, particularly the 1/2" nearest limbs. I often use some 1/8" to 1/4" laminations.
Good luck!