You couldn't grow above 1?!?
Could you elaborate on your situation there, terrain, tech choices, building choices, etc.
I am not surprised you found the game slow!
I have never experienced a zero growth situation, a lot of the time I am debating with myself as to whether growth is too fast!
If they aren't game breaking then don't worry about the messages, chances are they are platy UI related because I don't have all his 'vanilla' art stuff.
I am surprised you could not grow, with a vault civ even if your terrain is rubbish you can usually build up something with the buildings..
I suggest starting a new game, and if it happens again restart, as you have clearly been dumped in a bad situation, the mapscript is new and more or less untested, but we do know we need to add some kind of starting value optimization stuff so that players get more or less an even start. (my guess is you had a lot of rad wastes and a big health hit. Ghouls would have loved it, humans not so much!)
Also make sure to play on at least a large map, preferably huge, as this gives the mapscript the best chance of working 'well'.