Omega is the combined frontend and backend running the gaming experience. The EHA systems run emulation for various consoles and arcades. The frontend experience runs Launchbox. The backend or the individual emulators running various consoles, portables, and arcade games all use different emulators. Previous versions of the drives ran Hyperspin as its frontend with Rocketlauncher as its backend. Launchbox is actively being developed, enhanced, and supported by the community and requires a $75 license to run in what's called Bigbox mode. It's the pretty frontend everyone primarily uses.
ArcadeAdam posted a great Youtube video that explains the following when upgrading from Hyperspin drives to the new Omega drives.
There is also a full Omega Installation Guide for converting from a previous EHA drive (like a Manhattan Project drive) to Omega. It can be found on the EHA website under support. Here is the link: https://extremehomearcades.com/files/EHA_OMEGA_drive_install_guide.pdf
Find a quick start guide to get you going on Omega here.
The Omega Manual is your best resource for finding solutions to common problems with Launch Box, Big Box and the various issues you may experience.