This macro will create child configuration where all the dimension will be set to average value based on the minimum and maximum values of the tolerance.

Dimension Tolerance/Precision group in property manager page
Dimension Tolerance/Precision group in property manager page
Dim swApp As SldWorks.SldWorks
Dim swModel As SldWorks.ModelDoc2

Sub main()

    Set swApp = Application.SldWorks
    Set swModel = swApp.ActiveDoc
    If Not swModel Is Nothing Then
        Dim swFeat As SldWorks.Feature
        Dim activeConfName As String
        activeConfName = swModel.ConfigurationManager.ActiveConfiguration.Name
        swModel.ConfigurationManager.AddConfiguration "Average", "", "", 0, activeConfName, ""
        Set swFeat = swModel.FirstFeature
        While Not swFeat Is Nothing
            Dim swDispDim As SldWorks.DisplayDimension
            Dim swDim As SldWorks.Dimension
            Dim swDimTol As SldWorks.DimensionTolerance
            Set swDispDim = swFeat.GetFirstDisplayDimension
            While Not swDispDim Is Nothing
                Set swDim = swDispDim.GetDimension2(0)
                Set swDimTol = swDim.Tolerance
                If swDimTol.Type <> swTolType_e.swTolNONE Then
                    Dim averageVal As Double
                    averageVal = swDim.GetSystemValue3(swInConfigurationOpts_e.swThisConfiguration, "")(0) + (swDimTol.GetMinValue + swDimTol.GetMaxValue) / 2
                    swDimTol.Type = swTolType_e.swTolNONE
                    swDim.SetSystemValue3 averageVal, swInConfigurationOpts_e.swThisConfiguration, ""
                End If
                Set swDispDim = swFeat.GetNextDisplayDimension(swDispDim)
            Set swFeat = swFeat.GetNextFeature
        MsgBox "Please open the model"
    End If
End Sub