Debugging Help for an amateur programmer

I am a definite rookie when it comes to the API, and furthermore, to programming.  I am SO close to having my macro working, but I am getting an error that I need to debug.  This appears to be the final hurdle to getting my macro to function as I intended.

The debug error states:  "Object variable or With block not set".  Below is the line of code that is causing the error:

I think I know how to set a variable, I'm just not sure which variable to set or what to set it to.

I can include the full macro if it would be helpful.

Thanks in advance!

SolidworksApi macros