The server configuration files for Counter Strike Global Offensive differ from what you're used to with previous Source-based dedicated servers. The basics are covered in this article on Valve's website however I will cover the basics here;
gamemodes_server.txt
This covers the basic settings applied for each of the different game modes available in Counter Strike: Global Offensive. These settings are loaded when the server starts and applied whenever the game mode is changed.
You should not change this file manually as it will be replaced automatically by the updater in the event you patch your server after Valve have released an update, but you can use it as a basis for making changes by understanding the file hierarchy and applying it to the next configuration file:
gamemodes_server.txt
When you first install the CSGO dedicated server, this file is called gamemodes_server.txt.example and will need to be renamed. This has the same structure as the gamemodes.txt file and must remain in this structure to be read correctly. In this file you can define any custom settings you want and you can take any of the individual settings from gamemodes.txt and re-define them here in this file. When your game server is started the settings present in this file will override those loaded from the gamemodes.txt file. This is also one location that you can define your map cycle.
autoexec.cfg
This file is executed before the first map starts and can continue any individual server variables that you could otherwise provide from the command line.
server.cfg
This is your server settings file, and contains information like your server name, rcon password, maximum number of players, etc. If this file does not exist, the game server will not start.
This is not the limitation to all of the files you can create or use, however it is an overview of the ones that are required for the game server to start up to a point where people can connect and play. There are many websites that will cover each available setting in detail and even a couple of configuration file generators that will make the changes for you. As always before making changes to any configuration file, make sure you back up your existing ones first, so you can roll back any changes that you make in the future.
Best Answer
This answer is based on opinions from the community rather than facts provided by Valve.
The official answer would be: We don't know.
Kills do nothing when it comes to ranks.
The only thing that matters is whether you win or lose rounds.
Lose = you lose points (even with scoring an ace)
Win = you get points (even without killing anyone)
So if you're top scorer on your team and still don't manage to win more than you lose you'll have a hard time getting promoted. It's possible though.
How many points you get (or lose) depends on your current ranking (calculated in a system based on glicko2
*), the sum of your teams points and sum of your opponents points, and whether or not you are MVP**in that round.*Source**MVP will be awarded to the best performing player from the winning team. Usually defined by good teamwork (Bomb handling, kills, assists,..).