I have ToB installed so XP cap have to be 8 000 000, right? But this means 8 000 000 for each class for my multiclass F/M/T or 8 000 000 FOR ALL ?

The XP cap is total, so you could get a maximum of 2,666,666XP in each class.

So I have to get XP cap remover because the 2,666,666 is too low for me (although I am at chapter 4 I have about 2,500,000 now!)