So you have bought a 3.4 PAL Wii with a fully functional bootmii/boot2 install and you are complaining? The reason your Wii doesn't work is that someone installed Preloader on 3.4, which fails to work.
There are several ways to launch apps using bootmii/boot2. You can either launch apps designed to launch in Mini or use cboot2 to launch a Gamecube compatible Wad manager. Simply replace the bootmii folder on your SD card with cboot2 and change the boot.dol at root of SD to the app you wish to load.
You can also use preloader to launch a boot.dol of a wad manager.
All you need do to recover this Wii is install IOS50 v4889 here and then System Menu v386 here