Hi Slav!

This cheat worked for me:

Assume you have the path as /usr/bin/fldigi

At cqrlog/preferences/fldigi/wsjt interface set path to fldigi as:
/usr/bin/fldigi --wfall-only

Check Run fldigi after entering to remote mode.

cqrlog wants to find a file (from pah) that is entered in "path to fldigi". That's why you need to create a dummy file "fldigi --wfall-only" to /usr/bin
From console:
sudo touch /usr/bin/fldigi\ --wfall-only

you should now see:
[saku@hamtpad ~]$ ls /usr/bin/fld*
/usr/bin/fldigi '/usr/bin/fldigi --wfall-only'

Now cqrlog is happy when it finds that file and the run in background process handles that filename so that it calls "/usr/bin/fldigi" with parameter "--wfall-only"

Try!