You must manually toggle between input type when using your TWS to share content/presentation.
1. Using your remote:
Select VGA or HDMI for the "Secondary Input"
Press the Return/Back button to save or cancel
2. Using the web interface:
Log in using your web browser
System Settings>>Video>>Video In
Select VGA or HDMI from the drop down in the row for the "Video Input Name"
Press OK to save