I used this to select the circles with a given radius and change the color of the selection:
Dim selection1 As selection
Set selection1 = partDocument1.selection
selection1.Search "CATPrtSearch.GSMCircleCtrRad.Radius=0.125in,all"
Dim VisPropSet As VisPropertySet
Set VisPropSet = selection1.VisProperties
RedNum = 0
GreenNum = 255
BlueNum = 255
VisPropSet.SetRealColor RedNum, GreenNum, BlueNum, 1
Dim selection2 As selection
Set selection2 = partDocument1.selection
selection2.Search "CATPrtSearch.GSMCircleCtrRad.Radius=0.15625in,all"
Set VisPropSet = selection2.VisProperties
RedNum = 255
GreenNum = 255
BlueNum = 0
VisPropSet.SetRealColor RedNum, GreenNum, BlueNum, 1
Dim selection3 As selection
Set selection3 = partDocument1.selection
selection3.Search "CATPrtSearch.GSMCircleCtrRad.Radius=0.1875in,all"
Set VisPropSet = selection3.VisProperties
RedNum = 255
GreenNum = 0
BlueNum = 0
VisPropSet.SetRealColor RedNum, GreenNum, BlueNum, 1
selection1.Clear
selection2.Clear
selection3.Clear
However, I would like to know how to change the color of the elements during or directly after each element's creation.