The Covert Mission files have been renamed by me to follow the original WC naming convention.
ie. WC file extensions are .000; Secret Mission 1 files are .001; and Secret Mission 2 files
are .002. So, for Covert Missions (SM1.5) I set the file extensions to .015.

briefing.sm15 ~~~> briefing.015
camp.sm15 ~~~~> camp.015
module.sm15 ~~~> module.015
title1.sm15 ~~~~~> titl15.vga

Then, within the Secret Missions executable file (sm2.exe) I used a hex editing program to change
the .002 extensions for the three files to .015 and the title screen file name from title1.vga to
titl15.vga. I saved my changes to a new file named cm15.exe.

Using this method you can place the new Covert Mission files in the gamedat folder along with the
Secret Missions 2 files. Starting the game with cm15.exe brings you to the Covert Missions
title screen and off you go from there.