With regards to the cubes, notice that the strips don't always run parallel to each other depending on which kind of cube you're making. Also, it's very important to pay close attention to your placement of light, medium and dark values, within the block and also when you place them within the quilt. You should imagine a light source coming from one side, ie top right, and orient your cubes so that the light sides are all in this direction, otherwise the 3D effect will be greatly reduced and disappointing. Also, the points really have to match exactly as they are so obvious - after all the point of them is that they stand out, right? It's worth taking extra time and care with them. :-D
Here's the link again for those who haven't seen it yet
http://books.google.fr/books?id=btQ0...onders&f=false
:-D :-D :-D