How is your command set up? Actions are executed sequentially, I.E. one after the other, and unless the action has an option to be executed asynchronously (E.G. the "Wait until speech completes before continuing command" option for the "Say Something with Text-To-Speech" action), two actions should never overlap.
If your command is set up like this:
Press Right Ctrl+Right Alt keys and hold for 0,03 seconds and release
Click left mouse button
The right Alt key will be pressed, held down for ~30ms, and released, before clicking the left mouse button
To do both at once, you need to press the key first, click the mouse button, and only then release; E.G.
Press down Right Alt key
Pause 0,02 seconds
Click left mouse button
Release Right Alt key