The Cities: Skylines Mass Transit update (version 1.7.2-f1) was a significant 2017 patch that stabilized the game shortly after the Mass Transit expansion release.
The term "CODEX" refers to a known cracking group. While many community discussions on Reddit acknowledge that cracked files are often used to bypass DLC costs, there are significant drawbacks: MASS TRANSIT | Cities Skylines Beginners Guide Go to your steam_api
Fix: This is usually a crack issue. Go to your steam_api.ini file (in the game root). Open it with Notepad. Look for a line like DLCUnlocklist=. Ensure all Mass Transit DLC IDs are listed (DLC ID 715610). If not, add them manually. Ensure all Mass Transit DLC IDs are listed (DLC ID 715610)
When you see v1.7.2-f1 codex, it refers specifically to the cracked scene release of this patch for the Mass Transit DLC. Go to your steam_api
While the v1.7.2-f1 update was a milestone for Cities: Skylines, the "better" way to play is to stay current. Avoid the risks of outdated cracks and embrace the thousands of free mods available to official users that make traffic management a breeze.
The specific download string you referenced (containing "codex") refers to a cracked version of the game. Security Risk
The Verdict: The "better" version is not the stolen one; it is the legitimate version running on modern hardware with 100 mods from the Workshop.