Solved
I agree with Luc and Werner (below) that Prime will run this sheet.
The one you posted had obviously been converted from Mathcad 15 (all the red arrows are a giveaway.) I have Prime Express, and version 6.0 had no trouble until I got to the definitions of the gain; then I was told that "Im" and "Re" are premium functions. I was able to sneak around this,
and get the same plot as Werner
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