OKAY, the button I USED to dread, Button #5....

 Yes, I used to live in fear of Button #5.   But no more, because even though I don't precisely UNDERSTAND Button #5, understanding is not necessary.   No, I have walked through the Valley of the Glue Modes, and I have looked the Difference setting in the eye.   And I feared not the Difference Mode, nor it's cousin Subtract, nor even the mighty Procedural Minus.

 This button is actually called the Glue Mode in Blade Pro but it bears a lot of similarity to the Blend Modes in Paint Shop Pro.  This button controls how the filter is applied to the original image, and sometimes you can get neat effects, and sometimes you get nothing at all, but often times you get something very unusual!  The different modes control how the preset is applied over the bottom layers, so that that very same settings can result in dramatically different looks.

As much as I would like to tell you how the Glue Modes work, I think if I SHOW you the differences, it will probably be more meaningful ( and that way I sort of get out of giving you a highly technical gobbledygook explanation, too!) In all cases here, the initial image is the applied preset with Glue Mode, and the mouseover is the original image.  (In the case of the Glue Mode images, the original image is the preset in Normal mode.)