Can I use a normal UK Switch card and pin number (accessing my current account) in CVO autotellers the same way I can in the UK?

Yes you can, and if you have Maestro then you can use it in the Intermarche as well

We were in Carvoeiro in March (had a great time) and used Switch card no problem. One thing to remember is there's a small charge for each withdrawal that we don't normally get in the UK. Have a great holiday!!