appimage executables don’t normally show up in my applications menu so i have to create a new entry for them using the menu editor (Edit Applications…)
from there i can fav them, or pin them to the task manager, or add them to a the quick launch widget just by dragging and dropping.
it’s not clear what you mean by accessing the settings for an app… that would be an app specific thing (assuming it has settings).
there is application called gear lever that does some of this for you, if you want to check that out.