The key point here is that the GS mod has to be installed in the same directory as the original game. In the case of the Matrix release, the default location is :
'c:\Matrix Games\Commander Europe At War'.
I guess the main clue was the fact that the GS install had an empty 'jre' folder ; hence the missing 'java.exe'.
Next time I'll read though the earlier posts a bit more carefully !
Thanks, guys !

Folks,
Sorry this is bland but I haven't had the pleasure of using any 'forum' before !
My background game installation is Matrix v1.12 Gold.
I've tried the installation of the GS v1.6 package but it returns the above "not found" dialog. My attempt to then point this installer at the Java executable results in a big zero.
Subsequent attempts to start have had no response at all.
Can anybody offer some assistance ?
Cheers, Ron.