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To get a brief description of the different features you can check out this document which was put together by Steve Harris from several different posts of mine on Facebook.
To see how to set up several Turk's Heads described in Tom Hall's Introduction To Turk's Head Knots, check out this document which was written by Phil Scoltock.
In this document, Phil details how to use the grid maker to help plan out a very advanced knot using the Grid Maker (both in terms of sizing the physical knot, and using the grid maker to set it up).