Impressive, almos half good as original, sooo many years later...
Personally, Civilization IV engine is not very appealing to me, so I guess I wouldn't be really objetive when giving my personal oppinion about it, instead I'll just describe what I saw when I tried the game.
I have to admit also that I was kind of expecting the game being the original colonization just adapted to the Civilization IV engine, and it was, but in no way respected the clarity or the practicality the original had.
I chanllenge you to search for the game and give a glance to it, you will find that everything is perfectly clear on screen, explained and presented in a way where you understand what and how things work.
This mere mod, becouse is not more than a mod for Civillization IV, loses the escence that the original had, it made it slower, and took the fun out of it.
After a second read of what I wrote, I see there is not much actual information of the game, and it's becouse after playing the original so many times for so many time, even not far ago, and I just found myself playing Civ IV, not Colonization.