Hi again ciprianrusu,
Unfortunately, it does restrict what patch for R:TW you can download - it, sadly, disallows you from downloading 1.5 solo. However, you can still get 1.5, yet you have to install the 1.6 patch for BI at the same time. The two patches for R:TW and BI together in one file (1.5/1.6) can be located here. Simply install it, and then, with any luck, you hopefully will be able to sucessfully change the file enabling you to play as all the factions. Hope this helps, cheers!