What do you have that isn't working?
This is how I have my test project set up. My button mash in the plugin parameters has a total of 100 and a result variable id set to 56:
Then, in my event, I perform the button mash and after it is done check if variable 56 is equal to 100 (the total) or not, and if it is not I know the player did not complete the button mash. If it is I know they did complete the button mash: