The PC manual for the 4200 series isn't written well, but the necessary info is there - just hard to understand.
A couple of points that are under-stressed in the manual is the importance of staying with the recommended material dimensions, and the importance of measuring for the initial offset (the little piece you set to place the edge of the stock against. If you do both of those things carefully, the result is nicely symmetrical DTs. Otherwise, it gets a little messy, and you may end up with funky offsets that need to be trimmed after assembly.
Also, follow their layout suggestions and mark your stock accordingly. Without the markings, it's easy to get confused part way through.
Oh, and be sure that your corresponding pieces are exactly the same length, and that they are perfectly square. A shooting board comes in handy for that purpose.
There's a little stop gauge on the left for setting bit depth. If you use a piece of your stock to set that, adjusting the bit to the right depth is a cinch.
The newer OmniJig is much more versatile, but it's large, heavy and correspondingly more complex to set up. The 4200-series jigs are easy to get consistent results with regularly-spaced DTs (through or half-blind).