You don't need the 64bit version for linux to run more mods, you can just install http://forum.kerbalspaceprogram.com/threads/59005-0-23-Release-2-12-Active-Texture-Management-Save-RAM-without-reduction-packs%21 Ive got all majors packs like B9, KW, novapunch, Lackluster, fasa, kas, aies, aset, kethane, kspx, magicsmoke, mechjeb, nearfuture, romfarer, RLA, scansat, tiberdyne, etc.... And i have no problem with ram anymore my game boots at 2.1gb and after a few hours gets up to 2.8- 3gb at the most havnt had any crashes since the install.