The TechLevel configuration file is hardcoded to accept only a single file as valid: techlvl.odf . This file defines which Technology Trees are selectable in the drop down menu in the Advanced Game Setup window.
Stock Configuration ODF Commands
String, Default: Null
X determines the order of Techtrees in the drop down menu, starting with 0. If a Techtree is unspecified it will not appear from this drop down menu, but instead will only be available via the Map Editor in the Map Settings window. The appropriate Techtree file must exist in the techtree folder. File extension is required.
techfile0 = "tech1.tt"