As to the Craywood, Twickenham underprint all I can think of is perhaps they were for a casino that tried to get a license and were refused but chips had been made so they were reused (maybe they hadn't been gold stamped yet) although I'm a little surprised that they would have been recycled to be used on the QEII.
I have some Eclipse chips with stickers on (I took one off to look underneath once, world map style) and maybe one day I'll take all of them off to see what is possibly lurking beneath. Sorry, quick digression but they just popped into my head whilst this thread was unfurling.
Thanks again Michael, great research.