Well, it worked for me as it, most probably, should work: Strenght Training in Base until could start Fighting Training; More Strenght Training, More Fighting Training; More Strenght Training, More Fighting Training. (possibly a few times more both, I didn't count...) Finally, after Strenght Trainer said I have maximum in that skill, twice Fighting Training and after second time Alloting Points: 5 to each and clicking + to Power until said no points left.
So, no bug encountered in that part, as far as I understand...