OK, so I've learned several things:
1) I have no idea what I'm doing.
2) My FutureYieldTechs aren't researchable. Possible this has to do with the fact that they branch of the original FutureTech, and that one was still listed as "Repeatable". Corrected, and I will re-check later.
3) FutureCommerce doesn't seem to have an effect after a certain (currently unknown) game-point. If granted through WB right at 4000 BC, then it has an effect, but granted at end-game, no effect manifests. Reason unknown...
4) FutureProduction does work, but only if the city is producing Gold/Res/Cul/Esp. Again, don't know why.
5) I have no idea what I'm doing!!
(did I say that already?)
So, off to another week of work. Hopefully, I'll be able to tinker with some things over the next few days. EF, thank-you for the logging code, now I see how it works (kinda), and I think I can implement it to show where I've screwed up.
Thanks again!
1) I have no idea what I'm doing.

2) My FutureYieldTechs aren't researchable. Possible this has to do with the fact that they branch of the original FutureTech, and that one was still listed as "Repeatable". Corrected, and I will re-check later.
3) FutureCommerce doesn't seem to have an effect after a certain (currently unknown) game-point. If granted through WB right at 4000 BC, then it has an effect, but granted at end-game, no effect manifests. Reason unknown...
4) FutureProduction does work, but only if the city is producing Gold/Res/Cul/Esp. Again, don't know why.
5) I have no idea what I'm doing!!
(did I say that already?)So, off to another week of work. Hopefully, I'll be able to tinker with some things over the next few days. EF, thank-you for the logging code, now I see how it works (kinda), and I think I can implement it to show where I've screwed up.
Thanks again!

Read a lot of code to figure out what is doing what. It can be a PITA to read, but it gets easier as you do it more. Also, take notes. This would be perfect stuff to add to the Civ4 wiki's SDK section.
per city--no building required. They should work just like Future Tech that adds +1
to each city, only for yields.
Aussie, I can't thank-you enough. As a matter of fact, I think my wife may be even more grateful than I am, cause now I'm not so stressed about this! 