CSM Menu changes
The CUSTOM folder
To change MakePartImage (MPI) so that it always uses your own custom CSM menu whenever you make a .imgPTN file, you must use the CUSTOM folder in MPI.
You should never change any other folder. If you later add a new version of the MPI Tool Kit, you can simply copy your CUSTOM folder into the new MPI folder.
When MakePartImage runs, the entire CUSTOM folder will be copied to the partition image when it is made and will overwrite the existing MPI files inside the .imgPTN image. See below for details.
The \menu.lst file
Modifying the CSM Menu using the CUSTOM folder
To change the CSM menu, simply copy any of the files that you want to change (e.g. csm\menu.lst) to the CUSTOM folder (e.g. .\CUSTOM\menu.lst).The contents of the CUSTOM folder will be copied by MakePartImage to the root of the image after the payload\ISO has been extracted - any existing files will be overwritten by the files in the CUSTOM folder.
For example: You can place your own menu.lst or MyCSM.cfg file in the CUSTOM folder and it will be used by MPI. If you place your own 800x600 bitmap file at .\CUSTOM\e2b\CSM.bmp.gz it will overwrite the default background wallpaper (the file does not need to be a compressed .gz file and it can be a JPEG file instead of a .bmp file, but it must be named CSM.bmp.gz). MPI v0.085 and later will load \e2b\csm.bmp and \e2b\csm.jpg automatically, if they are present.
MyCSM.cfg - Changing the menu and wallpaper (v0.067+ Aug 2016+)
Design you own CSM Menu
Change the language of the CSM Menu
For older MPI versions
Using a 1024x768 menu
Updating the MPI Tool Pack
Add a GFXBoot Menu file
Testing the changes
Set a default menu entry and a timeout
Read more: http://www.easy2boot.com/add-payload-files/makepartimage/
Recommended for Easy2Boot (fastest!) - SanDisk Extreme SDCZ880-128G-G46