"Dummy" zwave switch?

Qolsys is considered Interlogix for the purposes of configuring the repeater?

Yes, you’re selecting the frequency the repeater listens for and transmits. Interlogix/GE is 319.5.

Can I have two of these, one as a repeater and the other as a translator?

You can’t have two repeaters, but I think one translator and one repeater would work, although I wouldn’t recommend it if it isn’t absolutely needed. PowerG will cover more bases, have more innate range, and be more secure than another unencrypted RF.

Sensors that I wish to “repeat” need to be cleared from the IQ2 panel and then learned again via the repeater?

Just learned into the repeater. I don’t believe there is any need to delete them from the panel.

The instructions weren’t clear to me on a point: how do I ensure that a particular sensor is learned into the IQ panel via the repeater, at a hopefully superior signal strength, as opposed to being learned by the IQ panel directly, but at a weak strength (the situation I have now)?

You don’t, if it is learned into the repeater it will repeat that signal to the panel. The repeater is just broadcasting that signal again. If the panel doesn’t receive it from the sensor, it will get it from the sensor.

What advantages are there for me as a DIY home user to cutting the lock jumper?

None. They lock automatically after 30 days. (I hate this “feature” but it keeps it tamper proof.)

Can a wireless pendent be programmed to turn on several zwave light switches at once controlled by an IQ4 panel?

Can a single press of a menu selection on the IQ4 panel turn on several zwave light switches at once?

Can the ADC app navigate to a menu item that turns on several zwave switches at once?

You can create a scene to control whatever you like in a single press.

Yes, also via a scene or by selecting them all.

Thank you, Trex.

Yes, scenes would be the way to go. On the IQ Panel 4 they can be used on the panel, and you can do so fro your phone app or as a widget on the home screen.