Ok, more trials and I got it:
Poedit work on .po files and such a file is found in the /languages/ folder of Inspira.
I was able to load the file and translate it into a German language file. Acutally quite simple.
It would help if you change the notation of .pot in you help file to .po in the sentence:
Then select the .pot file from the theme you wish to translate which you can find in the /languages/ folder of theme.