XF 1.5 Mybb 1.8 to XF 1.5

Hey community,
i want to import my old userbase from mybb 1.8 to xenforo 1.5.
So i use the import tool from xf but it says me that i can´t run the setup for users look screen:

Ist the import for mybb users to xenforo not compatible or did i making something wrong?
Regards, _nCo