kamikai
well the photon colors are coming from when it hits the solid, so you only need to separate a white beam into many. In the last 2 of mine, the two photon beams from the clone get split into 4 beams each, them bouncing those off the solids gives the 8 colors. BMTL acts as a 50% mirror, so if you make a diagonal line where it hits BMTL like you see in mine, half will go through and half be split. the most annoying part is that photons are still an energy type and will set off c-4 and burn acid so you have to make it so the photons never get within 2 pixels of it. photons normally go at a speed of 3 pixels a frame. they will 'jump' over anything in the first pixel after them, and will 'hit' anything on the 2nd and 3rd.
that should help explain something.