Below are requirements to operate Mask effect dialog in Multi mode:

1. EDIUS UI appears in continuous screen. For example, if three monitors are connected and you place EDIUS UI in primary and third monitor. Screen discontinuity occurs. In this case, Multi button won’t appear.

2. Do not place Windows Task Bar between of the monitors. For example, if you build horizontal multiple monitors and the task bar is placed vertically between of the screen, it makes screen discontinuity. Move the task bar to make screen continuity.

3. Do not set different scale value. Set same value for each monitor (you are allowed to set different resolution)