After searching for many way of getting past the bridge section, including using Cheat Engine, I wondered if downloading an older version would bypass the problem and work with achievements. Turns out it does! I realised this issue only started occurring after the update on February 7th 2025, so I downloaded the previous version and I was able to get the Hammer Time! achievement. You'll have to open the steam console and download the old manifest, then replace the files of the game so make sure you have the current version of ALTF4 installed.

Open your browser and enter steam://nav/console to launch the Steam console

You will be prompted to open the Steam app


A new "Console" tab will open up in the app



The command we're going to use is download_depot and the format is :

download_depot [app id] [depot id] [manifest id]

You can find all the information needed here[steamdb.info]

The command for version September 19th 2022 should be :
download_depot 1137460 1137461 4680156695888681236

This will download the files in the steamapps\content\ folder



Head to the old version's folder
"C:\Program Files (x86)\Steam\steamapps\content\app_1137460\depot_1137461"

and replace all the files in the current version's folder
"C:\Program Files (x86)\Steam\steamapps\common\ALTF4"


You should be able to launch the game. You'll know you have the old version running if you don't hear the balloon sound in the main menu and the "Play Together" mode isn't there.


Good luck!