Based on latest Steam builds for games and mods mentioned above: 47.1 GB
LumaEmu and SSE cracks applied for different games depending on their Steam API version, thanks to Steam006 and syahmixp!
Co-op_Launcher_v1.09-dekart811 & Portal_2_Co-op_Loader_by_Helifax are available in “Portal 2NoDVD” after installation
100% Lossless & MD5 Perfect: all files are identical to originals after installation
NOTHING ripped, NOTHING re-encoded
By default the following games/mods are installed with all text languages and English audio: Portal, Portal 2, Portal Stories: Mel, Aperture Tag, Thinking With Time Machine
Selective Download feature: you may skip downloading and installing of the following content: co-op/advertising videos for Portal 2, four additional voiceover packs for Portal and Portal 2, Portal Stories: VR, Portal 2: The Final Hours, Portal 2: Sixense Perceptual Pack and soundtracks
Significantly smaller archive size (compressed from cumulative 47.1 to 7.8~11.1 GB, depending on selected components)
Installation takes 15-30 minutes (depending on your system and selected components)
After-install integrity check so you could make sure that everything installed properly
HDD space after installation: up to 47 GB
Use “Portal Collection.exe” in collection root for game selection and changing their languages
Repack uses XTool library by Razor12911
At least 2 GB of free RAM (inc. virtual) required for installing this repack
Many thanks to Christsnatcher, who helped me a lot with this repack