I remember spending weeks searching for a copy of it years ago, Q1 and Q3 were everywhere but I wanted to play the story of 2. I finally managed to find a copy but it wouldn't work on my computer. Getting remade as open source is great news
No. This is only the game logic, ie. what mods modify. This is under GPL, though, so remaster mods need to comply to the GPL. The original's engine was open sourced long ago but the repository has no recent changes, meaning the remastered engine is unreleased in source form. The assets are fully proprietary as well.