I've managed to change the # of cars and frequency, the starting population, the lease length, # of years in a day and maximum size of the buildings.
I beat the game and the last scenario gives you 20 story buildings. I raised them to 25 to accomodate the large population of 50 000 that I set it to. The original setting of 500 people makes it impossible to make profit with the large buildings. I've also noticed that it is possible to change the starting commodities but haven't tried editing it yet as it would take some time.
To edit these settings you must have a DOS editer like XTree gold:
1) Go to the folder that contains Monopoly Tycoon and go to the scripts section.
2) Open the default folder and inside there will be files, one called default.lua and hub.lua
default. lua edits the car frequency. I've found that #'s 200 and over in the time sections 8to11 and 12to15 will result in a crash. The other time sections should remain low as those are the times of the night.
hub.lua edits the other settings except for the population and building settings. It is the file that is loaded when any level is loaded. This file also allows you to edit the profit recieved by the utilities and railroads.
To edit the starting population go to the folder of that level and load the hub.lua file. Inside it will have values for population and others depending on the level selected. You can also edit the starting money of course but if you're playing with the other computer players, they get the same starting money too.
Editing Building Size
Editing the building size can be done 2 ways
1. When you beat the game. The bonus level hub.lua file contains variables for the building sizes.
2 In the default folder, the file business.lua contains parameters for the sizes of the buildings and various other settings including tennant or stock capacity.
The bonus level folder is scena~21 in MS-DOS Mode. Although I have noticed the MS-DOS name of the folders vary from computer to computer as my brother's computer has them different. To find out which one yours are called run windows explorer and go to the monopoly tycoon folder where it is located and right click on the folder. Then go to properties and it will tell you the MS-DOS name which is only 8 characters long.
*!!Note: VERY important. Make back-up files of the files you are editing in case you mess up and crash your system. Also if you like playing linked games, all other computers must have the same files as yours or it will not work.
If anyone has any questions, feel free to e-mail me. Thank you.