But I have 5 different lenses and I find buttons can be sticky with all of them (1 empeg and 4 darkstorm) so every time I change I need to tweak the 2 nuts (ba-doom) on the left side to prevent this.

It could well be that some are a thicker plastic, but as it is a known issue even with stock lenses, I wouldn't bother pinning it on the lens. I would just adjust the fit until all is well again.