Some hours later. . .
It runs (so far to about 200 BC) with no crashes, BUT, after Editing it, the mod would not start up and I received a "Scenario Version Invalid" message on the main Civ III screen with a compatibility warning. (see image below).
Oh yes, I also noticed a lot of upgrades in Units had generic units upgrading to civ-specific UU's, and even UU's of one civ upgrading to UU's of a different civ (how is that possible?). Which I don't fully understand.
BTW, is uninstalling and then reinstaling the entire game necessary? It is a fair amount of work when I also have various unique saves, mods, and files to retain (such as the "less yellow" and Fascism options). In fact, it's quite a bit of work.
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So, here it is a little later.
I ONLY Edited the Diplomats and Spies section and I received the same notice: "Scenario Version Invalid".
I then pasted in the original #6 and only Edited the Resources section, yet I received the same "Scenario Version Invalid".
This is may be a serious apparent bug as the Strategic Resources are still way too rare in this mod and too prone to depletion, and horses and rubber should never be depleted. Coal and iron are especially too rare for me to be willing to play.
Also, even in LWC6 the Espionage functions are too expensive to be cost-effective. There are also various military units I need to Edit (less bombarding, for example), and some I wish to creat replacing the barbarian units I never use.
Even more curiously, I attempted to make a simple Edit to the basic game mod in the Civilization III folder - a small increase in the appearance of iron - I received that same error message I received while trying to Edit the LWC 6 mod.

The Editor used is the one that installed with the game, pasted in after saving after installing the patches.
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A little later. . .
I downloaded the NEW Editor from this site. I replaced the game Editor (the one before the patches) with that new one, and I Edited both the game mod and #6 - both of them now start as they should.
Soooo. . . . BEWARE THE OLD EDITOR! I suppose that was the problem. (I am not refering to the broken Editor that came with the first 1.17 downloads).
I have no idea if even this will prevent crashes at some point if we do Edit; it at least got the game started.
We shall see. . . later, tonight.