After a number of people tested their use with epoxy glue for me, I felt I needed to publish the results of those tests.
The bottom line is - Styrene does NOT glue well with epoxy.
If I come across a two part glue which does work - I will update this message.
If you have tried any glues and found them to work, I'd be interested to hear about them!
Use only Industrial Quality CA glue, and be sure to degrease with IPA (IsoPropyl Alcohol) and scarify the surface well (240 grit works well) before attempting to glue them to your wood or blade.
I have made a couple of knives using CA glue and styrene liners, and so far have not had any problems.
When in doubt - test your product before use - it costs less than a beer to buy an extra set, and not much more than a litre of petrol.