Great Spy:
Hmm I am not sure what happened with the great spy, I don't think I have ever had one but I don't think that should happen, could it not leave your borders? If that is the case I need to give it the special promo that lets it. We once discovered that spies could not enter an enemy town during war, only peace, but I actually quite liked this as a concept. But I am fairly certain they could enter territory, so not sure what is happening there. MAybe at some point I accidentally changed the entry or something, I will tak a look...
Map Scripts:
Yeah don't use great plains, it is a rubbish script, I need to remove it really because it just doesn't work... Pangaea is much better, but I think it still needs work and starting locations is another problem. I am not happy with the mapscript yet, but I can't do much to it with my skill level.. Ideally what I want is a pangaea style map where everyone starts on the left (of one big US/america style continent), like adding something that says each faction must start within say five or 6 tiles of at least one or two other factions so that you start with eveyone bumping shoulders really early, so you get lots of pillaging and squabbling going on right from the get go!
Borders and units:
It is only units with a strength less than 6 and no Intrepid promo (I think that was what I called it!) that cannot leave borders, the main reason I did this was to try and stop the AI suiciding itself into oblivion by constantly sending out weak units to die and then never getting above about size 4 with their cities...
But it is also about trying to slow down exploration, the eventual goal is like I said to have everyone together, so there is constant squabbling and an 'East Rush' to grab new territory, before Conquest comes into play.
AI:
I may go in and give the AI a bit of a bump help in the Noble Handicap setting, see if I can get them to be a bit more competitive, as right now the human player has a few tricks that the AI just doesn't understand and cannot capitalise on. I also need to expand the 'unit building' ai so that it does not get an uncompetitive unit cap at certain city size ceilings.
(I just need to decide what the math should be and then ask for some help to write it. Hopefully it is only a couple of lines of code.)
Production Costs:
You are probably right, it is going to take time to find the right numbers with costs, the more numbers feedback I can get the better, city sizes, improvements, terrains, etc, etc.
I do plan to add more buildings in the future as well, that will help capitalise on all the different resources, as well as expanding the number of resources and adding in building chains and requirements and making it all more difficult and detailed, some buildings I will want to be built quick (as they are just simple shacks and the like) but others will need to take a long time, like the factories and nuclear plants, labs etc. I also want to try and get it to the point where you really have to choose between things, so you won't have time to get everything in one place, etc. So maybe having really high costs for 'chain ends' so you can only get to the best of chains in a few things.
Building costs is an easy change to make, it is one number, in one file, for each building, the hard part is mathing out what those numbers should be with all the other variables in play.
The no growth mutants:
I would be interested to know this too, at one point they started with a bunch of negatives, but I think I got rid of all those.. hopefully giving the ai a buff for early on will get them going better, it could just be that they had an awful starting location, as terrain is much more extreme in this than vanilla. (Especially the Great plain which is just down right awful distrubution....)
Goody Units Problem:
We could go into the .dll and change the code and come up with an elaborate unit teleport system... or... we could just change the unit given by goody huts to something different, that can move outside borders and be upgraded to any kind of basic unit, or worker or immigrant

bit of an easier fix that way
