Hello @lveci!
My question is very similar - I also use GRD EW and IW data, and I would like to have nice wind fields. I follow your procedure exactly: Read --> Calibrate --> Wind field estimation, but every time I and up with a file with no wind information at all (so my output *.geotiff file contain only HV and HH bands, no wind vectors). I tried with different window sizes (from 5 km to 50), the result is the same.
It might be possible that the masking doesn’t work properly for me - if I choose “Mask out the land” with/without “Use SRTM 3 sec”, nothing happens as well (I tried this procedure separately).
As for Level-2 data - there is not much in my region of interest (Arctic area, e.g. the coastal zone of White sea), and if I understand it properly, by this moment L-2 is produced only from WV mode imagette that are really sparse.