Works for me. Note that when you select a shortcut file on the "Start-Up" tab, the target executable of the shortcut is filled in without the parameters. You have to add back the "www.facebook.com --incognito" part in the "Command" field.

i've been trying to have facebook and gmail start when dexpot starts by using the start-up option. but i can't set it to start in incognito mode (secret mode or in-private mode) is there a way? so far i've tried this: make another shortcut of google chrome. right click and go to properties. add "www.facebook.com --incognito" (not including the quotation marks) in "target"
the shortcut successfully goes into incognito mode and go to facebook when i click on the icon itself but when i have dexpot open it, it doesn't go into incognito mode even though it goes to facebook...