You cannot create a new kind of ActiveX object in LabVIEW, but you can use ActiveX to control LabVIEW (or a LabVIEW-built EXE) and run your VIs programmatically from other development environments.
Below is a modified excerpt from an
example provided by NI on running a LabVIEW VI from Visual Basic:
'--------------------
Dim lvapp As Object
Dim vi As Object
Dim paramNames(4), paramVals(4)
Set lvapp = CreateObject("LabVIEW.Application")
viPath = lvapp.AppDir + "\examples\apps\freqresp.llb\Frequency Response.vi"
Set vi = lvapp.GetVIReference(viPath)
vi.FPWinOpen = True
paramNames(0) = "Amplitude"
paramNames(1) = "Number of Steps"
paramNames(2) = "Low Frequency"
paramNames(
3) = "High Frequency"
paramNames(4) = "Response Graph"
paramVals(0) = cwnAmplitude
paramVals(1) = cwnNumSteps
paramVals(2) = cwnLowFreq
paramVals(3) = cwnHighFreq
' paramVals(4) will contain the value of Response Graph after running the vi.
Call vi.Call(paramNames, paramVals)
'--------------------