Jim-
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>1. First, I created the grid class using the class browser, basing it on another grid class that I have. I gave the class a name, but otherwise made no other changes to this class definition.
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>2. Then, I created the PRG file in which I defined the column and header classes.
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>3. Then, I used the form designer, and dragged my grid class object from the form toolbar onto the form, and set the MemberClass to the column class in the prg file.

Had you added any columns to either the grid class or the object on the form before you set the MemberClass? The only differences I see immediately (and I haven't experimented) are that a) I'm using VFP 8, and b) I set the memberClass in the class, before I created any columns.