I thought I had replied to this, but I guess not.
The Descartes version is a French reprint of the original Civilization. When Avalon Hill came out with "Advanced Civilization", one of the changes from Civ to AdvCiv was that there was one card per player, instead of 4 for 7, or whatever. Those that claim Civ is better than AdvCiv usually point to this change as what broke the game.
In addition to the removal of limits on civ cards, AdvCiv underwent many more changes. The AST changed slightly (in my opinion less difficult), there is no limit on how many civ cards you can buy, trading changed significantly (for the better IMO), resolution of calamities (you can't sit on calamities for several rounds), end game scoring... I know I am forgetting some stuff, but those are the basics.
This web site is devoted to a AdvCiv variant. So, it'll be difficult to compare the Descartes version of Civ to Velusion's version of AdvCiv. I think I have an electronic copy of the AdvCiv rules somewhere if you want a copy... Just let me know
mcbeth@broggs.org