Hi Wolfgang,
I did this :
1) Install aspell-en to get the English dictionaries for aspell
2) Set the var LANG accordingly in a Terminal window :
export LANG=en_US.UTF-8
3) Then, in the same context, I opened Gemas and tried to spellcheck the text :
And I got the same error :
pi@raspberrypi:~ $ opentool Gemas
2020-05-26 21:03:10.277 Gemas[2102:2102] styleoffsets ... guessing offsets
2020-05-26 21:03:10.281 Gemas[2102:2102] styleoffsets ... guessing offsets
2020-05-26 21:03:52.651 Gemas[2102:2102] Language: English
2020-05-26 21:03:52.651 Gemas[2102:2102] Service to start: (null)
2020-05-26 21:03:52.651 Gemas[2102:2102] Port: (null)
2020-05-26 21:03:52.652 Gemas[2102:2102] Failed to contact spell checker for
language 'English'