First, do you plan to buy a map from Alain with the speed limit removed? If yes, he will send you a revised version of 31255 for something like 50 euros. If not, proceed.
You can download the 31255 map from inside the app: Map>Open, in lower left hit download. It goes to the developer’s site where you can choose from stock maps. Do this for 31255. Save this ( the app will create a subfolder). Then try downloading 31255. This should work but don’t complete the download to the ECU. Go into the Penner map and export F1-F3, I(3-6) and A/F under Table, export. You need to give the exported tables acceptable names for Android, for example, AirFuel rather than Air / Fuel. Then open up 31255 and save it with a different name. Using that map, under Table, import those 5 tables. Save the revised map. You can’t export the ETV tables. For each ETV table (1-3), go into the Penner map, copy the ETV table, eg, ETV1, then open your revised 31255, scroll to ETV1, then hit paste. Save the file, go back to Penner until all 3 Penner ETV tables are in your revised 31255. Save the file, connect to the ECU, download the map.