Portals 2
The Basics
Lets begin with a simple room, I am going to use the exact coordinates I used for my Portal map for this tutorial. The room was a 400 unit height, and 600x600 on Width and Breadth. Create the room, texture it, and throw in a PlayerStart. Now we will add two boxes. This is the space where the Portals will be. Thanks to Inoxx from the Unreal team the portal boxes HAVE to be 64x64x64 or bigger. For this little map we are making make it 200x300x200 (height*width*breadth). Put it on the outside of the room but make sure the end of it is touching the room then hit on the subtract from world button. Now let's change the brush marker to 200x200x300 this will show the same cube but now to the side. Put it on another wall and extract the world (just like the figure). One thing to remember both of the portals have to have the EXACT same geometry as the other. One CANNOT be bigger than the other. Please make sure both of your portals are done correctly.

The Portals
Now we will create a sheet to do this click on the button all the way on the bottom of the toolbar that looks like a gray diamond. This will change the marker to a thin sheet, now right click on the sheet button and go to Sheet Properties make the Orientation Y-Wall to make it vertical and then the U value should be 300 and the V value should be 200, hit build. Place this sheet in front of the portal that it fits and then click on the Add Special Brush button and on the PRedefined drop down list, pick Zone Portal and your portal is set. Now go to the Sheet properties and change the values from 300x200 to 200x300 and then the sheet will change direction to the other portal. Put that on the cover of the portal like the figure and hit Add Brush*. If you did it correctly it should look like the next figure. *- If you don't see anything please Rebuild geometry and if you still don't see anything make sure you added the brush.

The WarpZone
Now we will link the portals together. Go to the Classes menu -> Info -> ZoneInfo -> WarpZoneInfo. Add a WarpZoneInfo inside each of the boxes make sure they are in correctly at the X and Y values. Now Go to the WarpZoneInfo properties by right clicking on the WarpZoneInfo tag (it looks like a cube with a question mark) and goto WarpZoneInfo. You will see two boxes OthersideUrl and ThisTag. Double click on Othersideurl and enter the value warp1 and then double click on ThisTag and put in the value warp2. Now go to the other WarZoneInfo in the other portal and go to its properties. Do the same thing as you did with the first one but this time the Othersideurl will be Warp2 and ThisTag will be Warp1. Close the box and you are two steps away from having portals.

Surface Properties
Now click on one of the sheets we put in before, right click it after its been selected and go to its properties. Check Portals, 2 Sided, and Invincible. Hit close and do the same to the other one. Now to test that your portals are correct click on the joystick so that its not a shady white. When you do that the sheet brushes should not be visible instead you should see right through them and see the boxes with the WarpZoneInfo tags in them. If you do see the boxes you can check that the portals are there by clicking Mode and Zones/Portals, the whole room should be one color except the portals should be different. If this is done correctly you are almost there. Just add lights around the map and then rebuild Geometry, BSP, and Lighting. Play the map and see if it came out right.

Mini-Portal Faq
I click on the joystick and I see black wholes in the map.