Using MCell to simulate diffusion along a fiber

Hi, 

Is it possible to use MCell to simulate diffusion of a walker along a fiber. The fiber has A binding sites in a helical geometry and the walker has n x A' binding sites (so different number of feet). 

I guess one option would be to specify each fiber site with a sphere (I could do that using some python scripting), but not sure how I could implement the walker.

Any suggestions are apricated.

Thanks,
Ajasja Ljubetič,
Reaserch Asistant Prof.,
Department of Synthetic Biology and Immunology, National Institute of Chemistry, Slovenia