StrokesPlus crashed on me each time I did Right+Wheel in the Training Mode. It shows "Please draw a longer gesture", then I get the normal Window notification if a program has crashed "StrokesPlus Executable has encountered a problem and needs to close. We are sorry for the inconvenience."
Yes, I was able to reproduce and will fix. Training mode is only intended for holding the stroke button and drawing a line, so I never included any checks to skip modifiers (including the wheel) and to not try to fire the Lua script on wheel tick.