Component parameter DC Sweep

I found the following thread trying to troubleshoot my problem:

https://community.cadence.com/cadence_technology_forums/f/rf-design/21507/working-with-dc-sweeps-and-op

I am trying to do the same thing shown here except I am trying to plot a device in a lower level of the hierarchy. I've created a save.scs file with the following lines:

save I0/Mcp:oppoint

save I0/Mbp:oppoint

I go to Setup -> Model Libraries and add the save.scs file to my global model files. I perform a DC sweep where I am sweeping the length of the device Mcp listed in the save.scs file but I am unable to get Cadence to evaluate the expression getData("I0.Mcp:gm" result 'dc). Cadence says the expression evaluates to nil. I'm running version 6.1.7.