hey cool i tried it...but i am not 100% hapyy with it

the cam dont work correct, as example if u have one portal on the top direct under the player and one on the wall and u look through the one at the wall the cam moving is a bit confusing...

and you can't go throguth portals on the bottom (the blue sprite is also wrong)

,but that are smaller things, really like it
if u now use a tga and some particle effects it will look great

(now i know why u asked for placing blood at the wall^^)