Is credting something as the source an indication of compatability or co-adaptabiity? The purpose of clause 7 is to prevent marketing blurbs on a product along the lines of "compatible with D&D" and the like. Is indicating, in the text, that a particular game element is sourced from another element a contravention of clause 7? I'm not sure where I see the indication of compatability or co-adaptability in that.Incorrect. You are constrained by clause 7. "You agree not to indicate compatibility or co-adaptability with any Trademark or Registered Trademark in conjunction with a work containing Open Game Content except as expressly licensed in another, independent Agreement with the owner of such Trademark or Registered Trademark."
You are more constrained than with normal trademark law, but I'm not sure to what extent.