There is a bug in "Logi Options+" 1.78.588966 relating to ‘Smart Actions’ where pressing first one key combination (e.g. Ctrl+Shift+‘x’) and then pressing another key combination (e.g. Shift+‘K’) does not detect the "modifier" key (i.e. the "Shift" key) and so it treat it as if only ‘k’ key was pressed (without the "Shift").
I'm guessing that ‘Smart Actions’ is looking at the keypress events, rather than checking the status of all the "modifier" keys.

Holding "Shift" and pressing ‘a’, ‘b’, and ‘c' in succession yields "ABC", as one would expect; but where ‘Smart Actions’ are involved, if the "Shift" key isn't pressed and released each time, then the status of the "Shift" key isn't detected except on the first key pressed.

For example, simple things like using a key combination Ctrl+‘something’ then, still holding the “Ctrl” key down, and then pressing the Right-Arrow “→” to move to the next word doesn't function properly.  The “→” press doesn't detect that the “Ctrl” key is still held down, and so it only moves one spot to the right, rather than to the expected next word.