I’m running Keyboard Maestro on a Mac with Catalina. In Pages, I wanted to trigger a shortcut with control-right-arrow (or control-left-arrow) but it refuses to trigger. Shift-right-arrow (or shift-left-arrow) triggers it, and all my other shortcuts work as intended.
There was some discussion about problems with Mojave in this regard, is this still an issue or am I just missing something obvious?
It appears the system preferences were taking priority over the Keyboard Maestro trigger, despite what many sources say. Try Apple > System Preferences… > Shortcuts > uncheck whatever might be conflicting your trigger.
I am having a similar problem with Control-right arrow in Mojave (10.14.6).
I have a KM macro that I have used successfully with that hotkey for some time to toggle palettes in Nisus Writer Pro. Suddenly, for no apparent reason, the hotkey is over-ridden by some system function to move the cursor to the end of a line (which is redundant anyway because Command-right arrow does the same thing). I have been through System Prefs with a fine tooth comb (including all Services), and the hotkey is not listed anywhere there.
What changed? Did a recent system update add a new text shortcut? Shouldn't KM be over-riding it anyway?
For the record, there are a couple of places where Control-[right/left] Arrow are used by the system without a configurable setting. Those shortcuts, for example, are used instead of Command-Arrow for moving to the beginning/end of a line in the Safari URL field and in Spotlight.
If you're still having trouble determining the source of what is using Control-Arrow, have a look at ShortcutDetective. The app is free and "detects which app receives a keyboard shortcut (hotkey). This is useful because sometimes you aren't able to register a shortcut in an app ... and want to know why."