Need CST macro that updates the structure when changing the parameter

I have write a macro that makes an universal antenna.

everything works but when I change a parameter in the parameter list I get a error:

Expecting an existing scalar var. (I=0)


Can anyone help me??

ps I'm sorry for my bad englisch I'm from germany




Here is the code I use:

' rotation2

Sub Main ()

GoTo Back

Exists:
Component.Delete "component1"
I=0
GoTo Back

Back:


' StoreParameter("t",1 )
' StoreParameter("b", 2)
' StoreParameter("lam", 20)'lambda
' StoreParameter("a", 5)'Winkel a
' StoreParameter("r3",7)'Innenradius Stufe3
' StoreParameter("r2",5)'Innenradius Stufe2
' StoreParameter("r1",3)'Innenradius Stufe1
' StoreParameter("l3",5)'Laenge Stufe3
' StoreParameter("l2",5)'Laenge Stufe2
' StoreParameter("l1",5)'Laenge Stufe1
' StoreParameter("d",2)'Wanddicke
' StoreParameter("l",100)'Laenge des gesammten Rillenhorns


a1=((90-a)*pi/180)


With Rotate
.Reset
.Name "solid1"
.Component "component1"
.Material "Vacuum"
.Mode "Pointlist"
.StartAngle "0.0"
.Angle "360"
.Height "0.0"
.RadiusRatio "1.0"
.NSteps "0"
.SplitClosedEdges "True"
.SegmentedProfile "False"
.SimplifySolid "True"
.UseAdvancedSegmentedRotation "True"
.Origin "0.0", "0", "0.0"
.Rvector "1.0", "0.0", "0.0"
.Zvector "1.0", "0.0", "0.0"




.Point 0,lam/2+r3


Do

'xx=I*b+I*t
.LineTo I*b+I*t,lam/2+r3

xx=(I+1)*b+I*t
.LineTo xx,lam/2+r3

xx=(I+1)*b+I*t
yy=(((I+1)*b+I*t)/Tan(a1))+r3
.LineTo xx,yy

xx=(I+1)*b+(I+1)*t
yy=(((I+1)*b+(I+1)*t)/Tan(a1))+r3
.LineTo xx,yy

I=I+1


Loop Until ((I+1)*b+(I+1)*t-(b/2)-t)/Tan(a1)> lam/4

cx=I*b+I*t
Cy=(((I*b)+(I*t))/Tan(a1))+r3

lange=cx+l1+l2+l3
I=0


Do

xx=I*b+I*t
yy=(lam/4)+((I*b+I*t)/Tan(a1))
.LineTo xx+cx,yy+Cy

xx=(I+1)*b+I*t
yy=(lam/4)+((I*b+I*t)/Tan(a1))
.LineTo xx+cx,yy+Cy

xx=(I+1)*b+I*t
yy=((I+1)*b+I*t)/Tan(a1)
.LineTo xx+cx,yy+Cy

xx=(I+1)*b+(I+1)*t
yy=((I+1)*b+(I+1)*t)/Tan(a1)
.LineTo xx+cx,yy+Cy

I=I+1


Loop Until (I*t)+(I*b)+lange >l


.LineTo cx+I*(b+t),((cx+I*(b+t))/Tan(a1))+ (lam/4)+d+r3
.LineTo 0,((cx+I*(b+t))/Tan(a1))+ (lam/4)+d+r3
.LineTo 0,lam/2+r3

On Error GoTo Exists
.Create
End With

With Rotate
.Reset
.Name "solid2"
.Component "component1"
.Material "Vacuum"
.Mode "Pointlist"
.StartAngle "0.0"
.Angle "360"
.Height "0.0"
.RadiusRatio "1.0"
.NSteps "0"
.SplitClosedEdges "True"
.SegmentedProfile "False"
.SimplifySolid "True"
.UseAdvancedSegmentedRotation "True"
.Origin "0.0", "0", "0.0"
.Rvector "1.0", "0.0", "0.0"
.Zvector "1.0", "0.0", "0.0"

.Point 0,r3
.LineTo -l3,r3
.LineTo -l3,r2
.LineTo -(l2+l3),r2
.LineTo -(l2+l3),r1
.LineTo -(l1+l2+l3),r1
.LineTo -(l1+l2+l3),((cx+I*(b+t))/Tan(a1))+ (lam/4)+d+r3
.LineTo 0,((cx+I*(b+t))/Tan(a1))+ (lam/4)+d+r3
.LineTo 0,r3

.Create

End With

End Sub