SPTinstall by Julian “Codec” Onions
This utility is used to rebuild the terrain files, it reads theater.L2 and theater.O2 files to produce the other levels L1, L3, L4 and L5.
You need to run this utility each time you modify the terrain or tiles.
This util was made by Codec originally but Fred “BaldEagle” Balding modified it to work with 4-byte offsets, plus added some code to adjust the elevations used for the generation of the L3, L4 and L5 data.
There are (or was more likely) two versions of this program, they were:
ntF4PTinstall - 2 byte terrain files.
SPTinstall - 4 byte (todays standard) terrain files.
This is how our Europe theater terrain is rebuild, the command line:
sptinstall.exe -auto d:\games\f4\theaters\europe\terrdata