Use a snippet similar to this Procedure
to set the start location (assuming you are using the Map component) . First, create the code below, then add a runtime Marker to your Map. Call the Procedure in a Button.
Use the code here How to put my location on a map - #2 by SteveJG to create the 'second' , moving marker showing your current location as you move around. The LocationChanged event replots your location as you move around.
To get this to work the way you want it to, you may have to experiment.
Did it work for you?
Regards,
Steve