BTB, this is a great idea !
The mod or the editor tech hack? >.>
As for the tech hack in the C3C editor... I'm not sure if I got the entire point across.
Here's the basic steps:
One, set all of the technologies you'll be working with to Ancient Times, starting with Stealth and working backwards. You must work literally one step backwards at a time, otherwise the editor will stop you. Any tech involved must be marked as Ancient, meaning I had to set the entire Medieval era back.
Two, make the desired changes to the prerequisites. Since everything is all in the same era (Ancient Times), the editor will allow this.
Third, starting again with Stealth, work one step at a time backwards setting everything to Medival ages. The editor will allow this change because it will let you change the era a tech is assigned to without altering its prerequisites (though it does get kinda crabby if you try to alter the prerequisites after the fact, so you have to make sure you've got them how you want them before moving on to this step).
Changing the era on a tech WILL mess with any techs that it itself has been assigned as a prereuisite for, meaning that when you are changing the era of a tech, any tech that it has been assigned as a prerequisite for must have ALREADY been changed to that era first. For example, the game has no problem letting you set Chivalry back to ancient times so that Monarchy can be made a prerequisite for it. It's just that anything Chivalry is a prerequisite for (in this case, Military Tradition) must have already beens et back to Ancient Times to avoid the editor messing with your tree. It's for this reason that you need to start with Stealth and work backwards.
If this trick did not work in the C3C editor, the editor would automatically freak out when you make the first step, which is setting Stealth back to Ancient Times.
In any event, like I said, you need to work in a long series of lines that gets a tiny bit shorter each time. Step three must be repeated several times in order for the trick to work. You can just follow step three by setting Stealth back to Modern Times. It needs to be set to Middle Ages, then to Industrial Ages, then finally back to Modern Times.
Hopefully, this explanation makes a tad bit more sense.
There are quite a few threads discussing tech trees. I don't recall ever seeing one where failure to have prerequisites from one era carry over to another (as a shortcoming of the editor) was discussed. Or references to the vanilla Editor having features that the Conquests Editor does not.
