On Monday, August 3, 2015 at 1:45:05 PM UTC-4, John Mittell wrote:
I have unchecked all but the critical warning. Does the vertical range
limit the number of warnings by displaying only those threats within the
bounds of vertical range. If so, what is a safe number, 500 feet?

Note the contest number of the person alerting you. Ask them to check that they are set as a glider in flarmcfg.txt. If they are set as a towplane/etc they alert a much wider volume than if they were set correctly as a glider/motorglider. This was a problem at the Chilhowee contest this spring; after a bit of effort, the last several days had vastly reduced alerts.