It's very easy to change this yourself (you do not need to unpack your game, and do not need to create a batch file to run it with the changes) go through the following folders:
Sega/M2TW/Data/World/Maps/Campaign/Imperial_Campaign
Open the file descr_strat
Just under the faction listings (which are at the very top) you'll find the following text:
start_date xxxx summer
end_date xxxx winter
timescale xxxx
Now change start date, end date or timescale to whatever you like. Note, timescale is what effects the number of years-per-turn and defaults to 2.00. It can be changed to either 0.50 (one year per turn) or to 4.00 (four years per turn) I do not think there are limits on what the start and end date can be set to, but remember changing the date effects whether or not, or when you'll see events triggered.
As far as changing event dates and editting building construction times, you will need to unpack your game before the correct files can be editted, and editting them will take some time. You will also need to then run the game via a batch file which you will have to create using the io file_first line.