you can do the glow thing with this dll: renderview

just copy this into your plugin folder, and then in script declare this function:
dllfunction render_backbuffer(entity);

then make a screen sized quad as a view entity and make a function where you call:
me=scree_quad;
render_backbuffer(me);

i recommend using a small skin texture for the quad. like 64*64..otherwise it gets slow. Then you also apply some postprocessing like blur..