No, I don't leave GC running. My normal actions are:
1. Launch GC
2. Import today's activity
3. Go to Trends and look at PMC
Except the PMC doesn't update, so I have to close and launch GC again
My PMC chart is set to show "days" and changing the date range does not force a refresh.
My system-wide calendar preferences is set to start of week = Monday (on OSX) but I can't imagine that would effect anything.
Skye