There may be instances that you will have pop-up modals in your app. When adding a step and a launcher to it, the launcher may place itself behind the modal. You can fix this by adding a z-index within the Launcher panel in the Authoring tool.
Changing the value of the z-index will change the position of the launcher. The increased value will bring it in front of other elements and decreased it will move it back.
There is also a possibility that the position does not change regardless of the value you enter. You may need to check with your front-end developer if there are any CSS from your application that might be overriding the settings of the launcher.
The z-index property specifies the z-order of a positioned element and its descendants. When elements overlap, z-order determines which one covers the other. An element with a larger z-index generally covers an element with a lower one.