Few questions regarding BI>Cycles

So I did some compositing in the Blender internal. Mainly few glow effects, a flare effect, sharpen at 0.2 on the main layer. Im wondering will the node tree I made will work if I render in Cycles and are there any restrictions when using cycles. I did few render tests and the lighting comes quite blown out.

Also. I would like to know how to mix specular values to a material in the compositor. For example, I want to mix Phong and Blinn on a material Im using.

Thanks in advance. I may not sound like Im making any sence. Im quite new to the compositor. Any info or a direction given will be very welcome.