I think the best you can do is an outdoor setup, with three or five very small ponds (better than a big one, more suitable for newts). Also the water level might be very low; about max 30 cm in the deepest point and only a few cm in the lowest point. The setup must be in a very sunny place, preferibly south exposed, because as you say, they really like basking! Also with air temperature about more than 30°C they love stay under the sun, in the low water point. Almost in every place, they do not tollerate the presence of large newts (ex:
T. cristatus) in theyr reproduction ponds 'cause they eat them tadpoles, so beware of this!
If you keep them in a terrarium, you might provide an UV light, and change it every year, because they need it as much as possible; like every
Bombina do.
Don't worry for the winter! They need it to reproduce well
! Make only sure you have a point of the setup with a lot of dead leafs and bark, so they can disappear in the cold period.
Don't forget to make sure they would not excape from the outdoor setup; and make sure also that any other animals would not enter!