This will assess your \maps folder for maps that are not on the official list, then give you a one button click to add them all to the extras.txt file. If already there, it won't add them again, so to add more maps as the weeks roll on, just copy the new BSP's to your maps folder, run this app, two clicks and they're added.

Written in VB express 2010, so you may need some sort of dependencies for that.

I've now added another file to download - setup.rar, which has the app wrapped in an installer which should check for dependencies and download them if not present.

File Name: Portal_2_Custom_Maps_To_Extras.rar
File Size: 38.49 KiB

Click here to download Portal 2 Custom Maps to Extras App

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It produces an exception, then nothing happens.

same here

Well... Try this Portal 2 Extras Menu Patcher

Just drag & drop .bsp file on this program and patch extras.txt.

The exception will probably be a dependency issue - I'll see about producing an installer for it.