[HELP] Fumefx on 3dsmax


hello im working on a school project and i wanted to add some fireballs on my character like shes creating them, its my first time using fumefx and im having some troubles.

The first is that i cant setup my flame size properly if i adjust the simulation area to low we can notice the fire being “cut” by the simulation box. as u can see on this print http://prntscr.com/m35u4w

Second is that i have 2 fireballs, one for each hand and they have precisely the same shape, is there any random seed property that im missing? thanks in advance good work to everyone and happy new year.