Trying to use external project

Hi I have a project that has API code in it, now the code is all tested I need to incorporate it in our main project but need the original project to continue to be separate.

I save the project as an external and then in the master project I added it as an external, however now I don’t see any of the code in the external.

Should I just save the Form and Modules as externals?

you must save ALL the project items as external (except App class) , and include them all in the other master project.