DH: So, with only one corp it works. hm. Try to add the second in parts. First only the corp. then the spreading unit. then the buildings...
New features of the next version:
Ok, I try to explain. For the trading stuff, I am very proud of because this is again something, that's not part of any game at the moment (the full feature)!
Spreading:
This is perhaps something that's not really new to you, as it is already part of some mods (I think) and Platys scripts.
In PAE I - and this was completely new as it is almost 8 years old now - you could spread wine with trading grapes and building a vintager. Now you will be able to spread/unset/set all distributable bonus resources yourself with a unit.
Trading:
This will be a completely new stuff.
A) Influenced by all the train simulations (Railroad, Transport Tycoon) and of course the Anno games, you will be able to buy bonus goods into your merchant (not matter what city) and sell them in another city. The merchant unit will not be disbanded now. Standing in the foreign city with foreign goods, you can buy them and carry them to one of your cities. The city where the trade has been done
is able to profit from the traded bonus resource for 10 turns. (Eg. dealing with bronze, the city can build bronze units for a short time). Different properties influence the value of the bonus resource (there are grain, livestock, luxury goods.. as well as the attitude of the foreign leader).
Some more things can happen when you trade goods:
1) Trade partners get some science points when trading
2) Influenced from all the books about famous trade routes: dealing with special luxury goods (I call them rarities ingame, like amber, incense, terracotta and so on) can create a trade road on a plot between the trading cities (=visible on the map). This trade road has the same properties as the Roman road but with +1 commerce point.
B) Influenced from Sid's Railroad, there will be special assignements with a time limit. Only maximum three assignements simultaneously, not more. It goes like this: A city wants a special bonus resource, independently if it's on the map (it's random).
If someone can bring the bonus goods into the city in time, he gets a reward. Either triple trade income or a special unit from this CIV.