Ok, I searched the forum and found this post by KLiM:
make .txt file, add text below and save him as EECH.reg
then run it and add information to registry.
[text start]
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Razorworks]
[HKEY_LOCAL_MACHINE\SOFTWARE\Razorworks\Apache Havoc]
"Installation Path"="D:\\GAMES\\RAZORWORKS" (edit for your EECH path)
[HKEY_LOCAL_MACHINE\SOFTWARE\Razorworks\Comanche Hokum]
"LANGUAGE"="ENGLISH"
"INSTALLATION PATH"="D:\\Games\\Razorworks" (edit for your EECH path)
[HKEY_LOCAL_MACHINE\SOFTWARE\Razorworks\Enemy Engaged RAH66 Comanche Vs KA52 Hokum]
[HKEY_LOCAL_MACHINE\SOFTWARE\Razorworks\Enemy Engaged RAH66 Comanche Vs KA52 Hokum\1.4.1.C]
[text end]
Didn't seem to work though, I changed paths, version number, etc. I guess there's not much else to try.