Well, I tried it. It updated my sacred2.exe with a new securom but unfortunately I was still blocked by a 'too many activations within timeframe' error. Once they raise my limit again I will try again.
Edit:
I can confirm the workaround works. I have restarted the game multiple times now and have had not problems.
ps. As I don't speak German I have copied the global.res file from a en_UK install to my de_DE install and can confirm the text will be changed to English. The only problem is anything added with the addon, ie. Dragonmage CA tooltips, will be blank.
Does anyone know where I can get English translations, or even explanations in German that I could google translate, of the Dragonmage CAs?