Make sure the game is installed and run it at least once to ensure all dependencies are installed and the EA App is updated.
(I'm not sure if this step is even required, but it doesn't hurt to do it)

Download and install:
Node.js - https://nodejs.org/en/download/prebuilt-installer
Git - https://git-scm.com/downloads/win
PostgreSQL - https://www.enterprisedb.com/downloads/postgres-postgresql-downloads (during installation you need to set a password for the user "postgres", let's say it will be "password123")

also download and unpack The Beat Revival project files (green icon with "<> Code" sign, then "Download ZIP"):
https://github.com/ploxxxy/pamplona-future
https://github.com/ploxxxy/catalyst-mitm

Launch the pgAdmin application, right-click on Servers (list on the left side of application) -> Register -> Server...
Set a name (eg. Catalyst),

on the Connection tab set "Host name/address" to "localhost".
Here you can set the "Maintenance database" ("postgres" by default) and "Username" ("postgres" by default) that you will use later.
Enter the password you set during PostgreSQL installation (eg. "password123") and enable "Save password?" switch, then click "Save" button (bottom right).

Launch PowerShell and change directory to previously unzipped archive "pamplona-future-main.zip". If it is in Downloads directory run:
or
(1 on screenshot - you can right-click to paste the previously copied command)
in the second command "$ENV:USERNAME" is an environment variable containing the name of your Windows user.
If you've unpacked it somewhere else, using these examples you should be able to figure out how to get there.
Now run (2 on screenshot - this requires Git to be installed).

In case of error "npm.ps1 cannot be loaded because running scripts is disabled on this system." you might want to run:
which will allow you to run `npm` only on current PowerShell instance.
It's more secure than enabling such policy to the whole system, but will require you to run such command after closing and reopening PowerShell.

If you stumble upon an error showing "ECONNRESET" and/or "code 128" you may try workaround mentioned in comments:

Originally posted by LunaSpear:

1. If your "ECONNRESET" error is followed with proxy related stuff, use command "npm config set registry http://registry.npmjs.org/" .
2. Run npm install, if it shows error again but this time saying "code 128" error, this should be the last issue that stops you from installing.
3. Download the files from https://github.com/ploxxxy/tdf.js and decompress the files.
4. Back to PowerShell, in the pamplona-future-main folder, run "npm install --save (paste the tdf.js-main folder location)".
There you go, npm install should work fine now, you can follow the guide then.

Once done, in the same directory create a ".env" file with the content:
DATABASE_URL=postgresql://[username]:[password]@localhost:5432/[database]
which with database/username/password from above goes like this:
DATABASE_URL=postgresql://postgres:password123@localhost:5432/postgres
To do this, you can use the following command in PowerShell:
(3 on screenshot)
If you are doing this via the GUI, make sure the filename is ".env" and not ".env.txt".

Two more commands to go: and (4 and 5 on screenshot)
Now your local server is running - do not close the PowerShell window.

To be able to actually connect to the server, copy contents of previously unzipped archive "catalyst-mitm-main.zip" to the game directory (so files like EA-MITM.ini, dinput8.dll and so on should be copied directly to the game directory, not inside another "catalyst-mitm-main") .
To open the game directory, in your Steam library, right-click Mirror's Edge Catalyst -> Manage -> Browse local files.

You can now launch the game, which will connect to your local server and allow you to earn achievements that were unobtainable after the server shutdown.


If it's running, but new game started instead of loading up your previous save state, you can check if new save game directory was creaded in the same path as "pamplona-future-main" (eg. Downloads dir) and try workaround mentioned in comments:

Originally posted by LunaSpear:

Copy the save games folder "Mirrors Edge Catalyst" from C:\Users\USERNAME\Documents\ to the directory where you put "pamplona-future-main"

Once you close PowerShell window and/or shutdown your PC, to run the server again you will only have to open new PowerShell window, then change directory to "pamplona-future-main":
or
and run:
After this local server should be up and running, waiting for you to connect.

If it's still not running you can try workaround mentioned in comments:

Originally posted by ¤ βℓооđч ¤ Nico-Kun!:

What seems to have help was deleting a bunch of files named protossl_dump_[bunchofnumbers] that were created in the game's folder.

As mentioned in comments, after uninstallation of a game there will be some leftovers that you might want to clean up.

Originally posted by Camper-Hunter:

A small tip: since the man-in-the-middle tool was used to capture network and still does, it creates packet dump files which if you play a long time will be several GB. Also when you deinstall the game from Steam, these additional files will remain. So feel free to manually cleanup once you're done playing, or from time to time, since these files waste a lot of disk space for nothing useful to players.
You can also deinstall PostgreSQL, Node.js and Git (provided you don't use them for something else, obviously) when you're done with the game.