Where has my computer stored Lineage II's downloaded data?

I started downloading Lineage II today, and I had about 20gb of space left on my hard drive. Then when it came close to around 85%, I received a warning telling me I have low space. I checked my hard drive, and for some god**** reason I had about 200mb of space left on my hard drive. How the hell did that happen? I cancelled the download because of it, but it still said I had 200mb left.The only thing I was downloading was lineage II, and it should have left me with about 12 gbs left if I had finished downloading it. I went to Lineage II's folder, and the entire folder only took up 20mb of space. So where did that extra 19.8gb go to? I checked the %temp% folder and deleted everything there, but only about 200mb was stored in there.