[NTG-context] CM Super HF Bright -- encoding?

Good evening. I wish to typeset a document using Computer Modern Sans Bright font. There is HFBright package, and CM-Super package. The first one doesn't include all letters used in the Czech Typography, while the other does. So I'd like to use it. Now, what of encodings supported by the package should I use? I tried: \mainlanguage[cz] \enableregime[il2] \loadmapfile[cm-super-t1.map] \definefontsynonym [Serif] [ebmr10][encoding=cm-super-t1] but all accented letters were spoiled. I've got the same result when I tried to substitute "cm-super-t1" with "ec", "ec-lm", and "t1". What mapfile and what encoding should I use? Your thankful Michal Kvasnicka