1. only if you install the mod switch version. The one posted by Maced0n.
You could make a second install of rtw to achieve the same effect with the regular version of rtrpe, but if you`re new at this, sticking with the mod switch would probably be the easiest way.
2. who would pay to manufacture the mod on discs?

It`s only available to download.
3. if you have extra room it wouldn`t hurt to make a backup copy of your game folder before installing any mod. Just in case you mess up. The second thing would be to be careful where you install it. RTRPE installs by default in an Activision folder, but newer versions of the game have a different path(a The Creative Assembly folder). If that`s your case make sure to direct the installer to where you have the game installed.