Just realised I have a newer version on my other Cortex Command install, fixes issues with the explosive bullet guns hugely.

Substance-D revolver / Sniper / Arbatel fixed to react with more surfaces now.
ZosEQ similar modifications.

The way I was making both these weapons work on older versions no longer works very well any more,
the quirk is still there in this version with rounds refusing to detonate as it should be,
but alot less noticable, though they are a little keen to do it in your face now!