Hi Dani,

There is no need for installation, only thing that is required to do is adding it to slicer through "extension wizard", "Select Extension" and choose the "MultiXplore" directory inside of the downloaded folder, new module will be added to the list of modules in 3D Slicer (under Examples category).
We are preparing a manual and a paper on this module that will be published soon.

I hope this helps,
Saeed