Geometry Optimization on a Filler-Packed Mesostructure?

Hi All,

I have a filler-packed mesostructure consisting of a coarse-grained water droplet on top of a slab of polymer. After I've filled the formers with my fillers, how would I perform a geometry optimization? I think Mesocite is the key, but I can't get the geometry optimization to work after trying a number of various settings (fails with unknown error).

Anyone have any ideas to get me going in the right direction? I have a feeling it's a quick fix.

Thanks in advance,

S.R.