I have found 2 different ways to do this.
- When you remote into the vnc machine right click the Input Director tray icon and select "No Screen Edge Transitions", this disables transitioning to another screens, to re-enable perform the same action.
-The better way is to setup an easy hotkey combination on the "Master Preferences" Input Director tab under transition options to enable or disable screen edge transitions, you can choose what you want but remember not to use any key combos that vnc uses, I personally use ctrl+alt+[ and ] to enable/disable.
Hope this helps.