This build's console region setting is European. This may mean Sega of America was testing the performance on European consoles.
Military Base is no longer accessible if the player selects level 3 from the main menu. It can only be played if the game is played from Level 1 just like the Final.
Military Base is now Map 17 like the final and it now has actual music.
The sound cancelling out has been fixed. The Chaingun now sounds like it does in the PC version. Monster death sounds also had this issue last build and it is now fixed.