lighting for digital

[spiz]

hi~
i just did my first headshot shoot yesterday. near the end of the shoot, i started getting light bursts in the shots and it looked bad. the set up was ghetto, but when the lighting worked, it looked good.
it was wax paper covering a doorway with lights shining and strobes behind it to illum inate it. then i had an attachable flash pointed behind me to trigger a slave flash used with an umbrella, and some shots i put a steady light on from the side also.
if i was trying to be artistic, it would be cool, but that wasn't the case.
my knowledge on conservative flash photography is very small unless i'm doing effects/artistic. can anyone give me a pointer?