Just buy the full version. Currently blocked at level 19... I'll beat it!
So far, so good. I'm happy I kept track of level codes. So I started at level 9 instead of 1 :)
2 years ago(+1)
The trick is once you can get to the top-right corner of the map, first make sure you already have a portal placed next to the pressure plate, then go to the top-right corner, put another portal there, then leave the torch down in a place where you can see both portals and the pressure plate.
If still stuck, email me at "haplotenebra -at- gmail dot com" and I'll send you a video.
