Place the MS file in …\3ds Max 20XX\ui\MacroScript\ Look in the monsterBlues category after you restart max to bind to a hotkey.
Assign this macro to a hotkey, also assign Shift + the hotkey. For example, if you assign the script to the “D” button. Also assign Shift+”D”.
Pressing the hotkey will add increments to your selection. Pressing shift + hotkey will reduce increments. Also I set an upper limit of 5 and a lower limit of 0. You can open the script in a text editor and increase the upper limit.