Most build behavior is configured once, globally, in Settings. A few things, though, belong to the individual project — OPAL keeps those in per-project settings, keyed to the project’s path.
Engine pin
Each project resolves to an engine. From the project’s settings you can pin it to a specific installed engine (the same relationship the status & health page describes recovering when it breaks).
Build tool override
Globally, OPAL uses one selected build tool (see Build Tools settings). A project can override that with its own build tool when it needs a different generator than your default — otherwise it inherits the global choice.
Launch arguments
Set extra command-line arguments to pass to the O3DE Editor when this project launches. Useful for project-specific flags without changing anything global.