I ended up with my own model. Just in case anybody is interested the ready-to-use furniture library containing it is available here:
https://drive.google.com/uc?id=0B0C-6ov ... G54SllDSGM. One can import it in SH3D via Furniture->Import furniture library. Note that I made only 1 window sash (of 2) to open, which is my case.

Sorry if it's not perfect, that's my first experience.