Shift + Scroll vertically is messed up and turned into scrolling vertically

Note: Before bug reporting, please make sure you have tried the latest (alpha) version of BetterTouchTool and that you have already tried to restart your system :-). If you encounter a crash, please attach a crash log from the macOS Console.app from the "User Diagnostic Reports" section.

Describe the bug
Since I upgraded my rigs to macOS 10.13.6 the shortcuts I heavily rely on combining modifier keys with the normal mouse's scroll wheel horizontally and vertically are messed up.
As soon as I hold SHIFT down and scroll vertically it is turned into scrolling horizontally. BetterTouchTools fires all kinds of shortcuts I programmed to horizontally scrolling although I am actually SHIFT+vertically scrolling.
This is hitting my personal workflow very hard since I rely on using the scroll wheel with both axes and all combinations of modifier keys to edit audio inside AVID Pro Tools.

Affected input device (e.g. MacBook Trackpad, Magic Mouse/Trackpad, Touch Bar, etc.):
Normal Mouse, it's a Logitech Performance MX used without a special driver or app

Device information:

  • Type of Mac: MacBook Pro 12.1, Mac Mini 6.1, Mac Pro 5.1
  • macOS version: all on 10.13.6
  • BetterTouchTool version: all on 3.401, but I also tried a couple of earlier versions

macOS translates shift+scroll to horizontal scroll, maybe this was recently added to 10.13? (I though it has already been like this for a longer time, but I don't know).

Unfortunately I have no idea whether this macOS behavior can be disabled ;-/