A downloadable challenge

I got this challenge idea when I was playing PortalSnake's sandbox mode and was messing around with the three black portals. I decided to make this as a challenge so that you can try it out too.

Link to the original game is in the "More information" tab, but you can just click here too if you don't want to scroll all the way down.

RULES

Get ready for a LOT of reading !

Start :

The challenge must use all snakes (except the infinite one).

The build area's size must be 23 tiles long and 18 tiles large. You can just place walls at the two edges of the sandbox level, like so :

How to play :

First move all of the 7 portals inside the build area. The size and orientation of the portals doesn't matter, but there are more rules you have to follow that I'll get to later.

You can't place any walls in the area. Only move portals.

Once you placed everything, click the play button and let the game run for a while. You should probably set the speed to maximum for this.

When you get into a situation where none of the snakes can be cloned by the black portals and are stuck in a loop, set the speed to minimum (this doesn't mean all the way down) and start counting the points :

You gain 1 point for every snake that can't move at all.
You lose 3 points for every snake that can still move around the level. That's why not pausing the game is important.
If a snake is still inside a black portal, that snake and his clone counts as ONE snake as a whole.

For this, I'd recommend to take a screenshot, a calculator and some notes, then draw a symbol on tiles that contain a snake head. Be careful when doing this, especially when you count the ones that are inside portals !