Highlight Method in VBA & MD6

Hi;

I'm having a little trouble with the highlight method in VBA. In the
following snippet, I'm selecting a MD part, testing each feature and, if is
a drilled hole, I'm trying to highlight the edges that a hole is referenced
from and pop a dialog box with the distance.

Everything works except the highlight. I get the error "Generic failure to
execute operation with the provided arguments." I can't find what I'm doing
wrong in the help files. Any suggestions would be greatly appreciated.


Sub ParamTest()
Dim objMcadApp As McadApplication
Dim objMcadPart As McadPart
Dim objMcadParam As McadParameter
Dim objMcadFeat As McadFeature
Dim objTestDescr As IMcadDescriptor 'McadCounterSinkDescriptor

Dim colMcadParms As McadParameters
Dim colMcadFeas As McadFeatures

Dim util As McadUtility
Dim pick As McadPick

Set objMcadApp = Application.GetInterfaceObject("Mcad.Application")

Set util = objMcadApp.ActiveDocument.Utility
Set pick = util.pick("Select Component", mcBody)

Set objMcadPart = util.GetObjectFromPick(pick)
Set colMcadFeas = objMcadPart.Features

For Each objMcadFeat In colMcadFeas

Select Case objMcadFeat.FeatureType

Case mcDrilledHole
Set objTestDescr = objMcadFeat.Descriptor(True, True)
Dim locs As McadLocators
Set locs = objTestDescr.Locators
Dim curve As IMcadCurve
Dim loc As IMcadLocator

For Each loc In locs
If TypeOf loc Is McadDistanceLocator Then
Set curve = loc.Object
curve.Highlight True, 1
MsgBox "Distance from edge = " & loc.Distance
curve.Highlight False, 1
End If
Next
Case...