Hi RonJon,
Would you please share some of your settings to properly print PCL filament (speed, extrusion temperature , etc) ? What do you mean with 'aftermarket modrifications' ?
I also make homemade PCL filament from pellets with the filastruder: I obtain a rather fine 1,75 mm filament at a 70-80°C temp. The molecular weight of PCL might be of importance regarding the viscosity of the flow, mine is around 80,000.
Unfortunately I have troubles printing the PCL filament using my FDM Volumic printer (it is based on a J-head); I had some encouraging results at a 128°C extrusion temperature, but now I have the same problem than you with the filament not being pushed in, so I would be so happy with some advices making it run like a Cadillac ;-)