1×10 set up. Looking at swapping my current 36t chainring to a 32t, but as the bike is fitted with a chain device and guard I wondered whether ring would do or does it have to be a narrow wide?

I would

Yes, why not?

If the device keeps your chain on, then I don’t see the advantage of NW.
But it might let you remove the device, should you want to.

If you have a chain guide of course a normal ring would/should do, but why bother when you can get a narrow wide for almost the same price and maybe even loose the guide (unless you dh of course).

Edit..beaten to it 🙂