Well i kind of solved it myself in a diffent way.
It was in the code i posted, just wanted to mention had a bid of problem finding a solution 
Code:
Public Function MyTimeReturnMillisec(TimeCheck As Date) As String
Dim Min As Integer
Dim timetekst As String
timetekst = "0"
' Didnt want to go above 1 hours!!
If Hour(TimeCheck) > 1 Then
MyTimeReturnMillisec = -1
Exit Function
End If
If Minute(TimeCheck) > 0 Then
timetekst = Val(timetekst) + ((Minute(TimeCheck) * 60) * 100)
End If
If Second(TimeCheck) > 0 Then
timetekst = Val(timetekst) + (Second(TimeCheck) * 60)
End If
' Here i get the millisec
Min = Format(TimeShow, "ss") & Right(Format(Timer, "#0.00"), 2)
timetekst = Val(timetekst) + Min
MyTimeReturnMillisec = timetekst
End Function
But if the code can be improved it some have... maybe make a post "code it better"
So posted it her
Edit:
But looking at your code seem like a much better way anyway.