What is the checksum. If its zero it isn't reading the mod, and there is probably an extra folder in your mod folder that is preventing the game from reading the mod correctly (happens with certain extractors).
Basically, make sure the mod path is
mod folder -> SGI mod -> GameInfo, Textures etc.
and not this (which would cause your problem)
mod folder ->SGI mod ->SGI mod -> GameInfo, Textures etc.
edit: its for version 1.051 not 1.015 right?