I started with the 3rd person example project, substituted a MakeHuman character mesh for the character, and added a camera component connected to a neck socket to be used as a 1st person camera.
In the character event blueprint, I created a key1 event hooked to a toggle my first person camera active.
The 1 key switches the view between the two cameras.
However, when I save the project and reopen the project, the logic is shown in the character blueprint but the key no longer works.
If I then delete the logic from the blueprint and reenter it, it works again as long as I do not quit the project.