Play as P-Body and atempt to get out of old aperture through puzzles and tests to make sure you don't get replaced! You should have BEE2.4. Download it Here [github.com]. Click the newest version (Version 22 works on 32 and 64 bit systems now) and wait for it to finish downloading. Then, download the BEE2 items Here [github.com] . Click the "clone or download" button and click "zip". First, go to downloads in the file explorer and click on the zip that is NOT "BEE2_items_master". Unzip BEE2.4 in any location and then unzip "BEE2 items master" in the same folder as BEE2.4. Go to bin and find BEE2.exe and choose the location of Portal 2 (Usually either C:\Program Files\Steam\steamapps\common\Portal 2 or C:\Program Files(x86)\Steam\steamapps\common\Portal 2 and choose Portal2.exe. Now BEE2.4 should be running properly and remember, it will take a little to load.