I have been testing your civics and I have come twice to the same problem.
The second time I tested it I was in turn 84 or so and the first time happened more or less at the same turn.
The game simply gets stuck. I return to windows desktop but I can't see the debugger. I have to switch off Colonization from the task manager.
Here I attach the problem. You will find the normal bug of "City Lacks Plotgroup" but after you ignore it,there comes the problem.
In the meantime, I have been able to see a Nobleman appear after city growth, so civics work. I couldn't establish trading posts or missions so far.
Hmm, we need to work out a system that makes testing saved games easy as your mod name is imbedded into the saved game. It looks to be something like "Medieval Tech 2.0 i -civics". We should pick a standard name for anyone who wants to test to use, so perhaps
Medieval_Tech_Civics will do.
The main thing right now is to just test the civics to be sure they are acting as we say they should be acting. You don't really have to play through a game at this stage. Do you have cheat mode activated? If so you can press K to research any tech for testing. Look at the Pedia hints for other cheat commands.
So, if you wanted to test the new Trading Post connected Civics, you can actually Play as the Anglo-Saxons as I have given them all the techs necessary in order to test that, or you can Press K to get the tech for free in order to test.
When play testing try to think of ways to exploit the system to your advantage, or break the system. Test how the functions, commands, effects, etc. work; checking the numbers to make sure they are what they are suppose to be.
For example; you can set up several Trade Posts in barbarian villages with out roads. Then check your cities to see if you have a bonus, then change your Civic to "Free Market", and check your cities again. You should still not have bonuses. Then you can open World Builder and add or remove roads to connect your cities, then check for the bonuses again, there should be bonuses. Then declare War on the Barbarians, or change your Civics again, and then check to see if the bonuses are gone.
As far as I know World Builder should work with all the Civics for testing. You can add buildings, or units and change their profession if need be. The ability to change to any profession is not available in vanilla World Builder but is something I added for my own testing purposes.
Note: World Builder could break testing some features but if I discover this I'll make note of it.