For SIGNAL and REV X-LOOPS, there is a full User Guide that can be found in the 'Documentation' subfolder of the instrument's library folder. In addition to the PDF User Guide, we created an interactive help menu that will explain the function of each button, knob, and parameter when you click the '?' button (pictured below).
REV does not currently have a User Guide, but there is a help menu that's accessible via the '?' button. The '?' is located in the same place for REV X-LOOPS and will display descriptions of functions for all knobs, switches, and faders on the GUI.