slide out menu

I want my custom menu to be available at all times, but not visible at all times. I see a small graphic of some kind on the left edge of the screen at all times, and if the learner clicks it, the menu slides out over the current screen so the learner can choose a different lesson. On that menu will be another small graphic that they can click to 'retract' the menu.

I've put the menu on a master screen and seem to have it all working, but when the menu slides in, I want it to display on TOP of the current content of the screen and I want any buttons, etc., on the screen to be inactive until the menu has been retracted.

I've brought the menu buttons to the front, but they still display behind the text/graphics on the current screen. And I've tried moving the items on the screen to the back, but neither seems to fix the issue. And having the screen items on top means that any interactions on the screen are still active even though I put a transparent box behind the menu buttons.

Seems like until I can get that content on the top layer, this won't work the way I want.

I believe if I put the menu on a layer, I could set it to disable interactions on the base layer, but I don't want to have to have the menu on a later on every screen!?

Any ideas?