no SSS in RT?

[Komposer]

whats the reason, that I cant render SSS with RT engine? (CPU)

[t.petrov]

SSS requires a prepass, so it can't be supported in RT rendering (all things requiring prepass are not supported).
Hopefully we will implement a prepass-less SSS material in the future, it is in the TODO, but we've not come to it, yet.