I suspect your problem is not your setup (set 2 traces, one to LOGMAG and the other to Smith Chart) but rather your ability to interpret the Smith Chart. Suggest you search YouTube for "Smith chart tutorials" and ground yourself on those. Most of these videos consider a single point ONE FREQUENCY as it appears on the chart. Once you realize all the lines traced on the chart are just a collection of individual points tracing positions on the chart for each frequency in the range of frequencies you are sweeping, it will cease to be a mystery