When I add apps do I need to compile and install everything?

[aparker21]

I plan to copy at least one of the clock apps to update the background to one of my own design. When I do so. . .first, what do I need to do in order to make sure that gets done correctly? I will be using my own png file for the background and can use the programming of one of the watch faces and just make sure it inserts my png file as the dial or background. When I do all of this, do I need to run the compile.sh and then install.sh again, and do I need to compile and install everything every time, or can I somehow only update to the changes made and have those installed?