Hello,
The Start and End position refers to the "absolute" start/end position, i.e. from where a robots starts a SRC file and where it ends. You can choose to end with a HALT position instead if you e.g. want to end with the last LINear movement command.
If you are using the most recent member version, the start and end simulation is simulated in the regular robot simulation. In the trial version, you have to enable smooth simulation and add a slider to the smooth simulation input to see the first and last position.
Don't hesitate to contact us if you've got any further questions or need an example file.
Best,
Johannes