Ok, no problem.
Well, the picture preview is showing the old version that is no longer in use, due to WG changes to the game client it's not possible to allow to switch regions like that.
The mod is not converting your client, it's installing a proper changes to res_mods only. If you want to return to desired region either reinstlal the modpack and select your new region, or use WoWS Realms Tool, that is allowing to change regions without reinstalling. It's at the apps section.