Welcome aboard Hemlock73
To this old captain your English sounds perfect, but then again I am not a native English speaker either.
If you follow Vecko's detailed instructions, TWoS' installation is not that complicated. Probably less complicated than having to create your own mod list. If memory serves me well, recently some issues have arisen between TDW's game patcher (which is an important part of TWoS) and the game version sold on the Ubi Store, but since you already possess a game key, I think you could re-install the 'sparrow' version you had previously downloaded, and register it with your valid credentials.