Open the computer rmonitor you are using in uvmapper. (free will do)
Look at the space on the map for the screen. (you can export a blank map from uvmapper)
Resize the captured webpage to fill the screen area.
Save texture and plug that texture in the Diffise.
Better yet.
Put it in ambient and set ambient _value at 1 or above.

A computer screen emits light :-)

Poser 1, 2, 3, 4, 5, 7, P8 and PPro2010, P9 and PP2012, P10 and PP2014 Game Dev
"Do not drive faster then your angel can fly"!