Well, I do have geranium maculatum which is not a bigroot, much taller, and is a definite lavender color. I also have a couple in the sanguinem group and it's not one of those if it's fragrant. Of the bigroots I have Karmina, Bevan's and Ingwersen's. Bevan's is brighter pink, Ingwersen's is paler. Karmina seems about right if your photo is fairly accurate on color. I don't see why the seeds wouldn't get dispersed just like any other plant.
