well when you downloaded the file there shoulldve been a readme included, or go back to the page on simtropolis. Anyways, all necessary files should be linked.
Okay, call me crazy, but I was you i'd delete everything and start over, this time looking over the dependencies. Just would make things easier
when you've got everything you want all together, there's this tool called DATpacker on a site called
sc4devotion, that will condense your plugins and your game will run faster