Is there a way to only re-install the editor?
Or, does someone else know a solution to this?
No, the Editor is fine, it's the game that seems to have a problem.
The installer writes the following Windows Registry Key:
HKEY_LOCAL_MACHINE\SOFTWARE\Infogrames\Civ3PTW
which contains a number of values, for example
Install_Path = <where you installed Civ3>
When Windows introduced 64bit, the Registry was split in two parts: one for 32bit programs (like Civ3) and another one for the new 64bit programs. (No idea, why Microsoft did this, in my opinion, it only causes problems and confusion...)
Anyway, in a 64bit Windows installation, the keys for the old 32bit programs are now found in a special sub-folder, e.g. in our case:
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Infogrames\Civ3PTW\Install_Path
And also, in newer Windows version, programs sometimes need special permissions to access the Registry.
So what does this mean for our problem? The above error message "Could not locate Civilization III: Play the World. Please make sure the game has been properly installed" looks to me like the Editor is trying to read the above Registry Key (in order to find out in which directory all the art files, maps, etc. can be found), and for some reason doesn't find that key. It then assumes, that the game has not been installed... Why is the key not found? There are two possible reasons:
- The key is there, but the Editor cannot read/find it. (E.g. because of 32/64 bit registry mismatch, missing permissions, etc.)
These kinds of errors are probaly solved by what Civinator mentioned above: run the Editor in "XP Compatibility Mode" (solves problems with 32/64 bit registry confusion) and run it as Administrator (solves permission problems).
- The key does in fact not exist.
If the tips above didn't help in your case, then this is probably what happened in your case. You can check this by starting the program "RegEdit" as Administrator and then checking, whether the following path is there:
Note: in addition to this one, I found two more, which may also be relevant:
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Firaxis Games\Civilization III - Complete Edition\INSTALL_PATH
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Infogrames Interactive\Civilization III\Install_Path
Probably this depends on which exact version/edition of Civilization III you have installed.
If none of these exist, the next question is: why? I learned recently that only programs that run as Administrator, are allowed to write to the Registry. So if you did not run the installer with admin permissions, it would not have been able to write its registry keys, and this would explain why the Editor now cannot find them.
Solution would then be to reinstall the game, but this time as Administrator.
You could also try to create these three keys manually and fill them with the correct directory, where you installed the game, but I doubt this will be successfull. Chances are, there are a couple dozen other keys, that the game and/or Editor also expect, and which are still missing...