In the architecture of Resident Evil 4 (specifically versions prior to the 2023 remake, such as the 2007 PC port, the Ultimate HD Edition, or the Source Next version), game data is not stored in simple folders. Instead, Capcom packed environments into compressed archives. The "Layout" file is a binary container (hence .bin ) that dictates the of a specific room or area.
This usually means the game cannot read the structure of the new .bin file. This happens if the layout file was made for the 2005 port but you are trying to use it on the Ultimate HD Edition. Resident Evil 4 Layout Bin File Download
If you want to dive deeper into custom gameplay, I can help you by: In the architecture of Resident Evil 4 (specifically