welcome to CS!!
yes, the Rocky DL can clump a bit: when i had mine i used a cut-back small yoghurt container which fitted tightly in the top of the basket (cut bottom of yoghurt container out, and trim cup to about 3 cm) to catch the grinds, then stirred the clumps out with a toothpick, needle-stuck-in-cork or such.
good grinder, though!!