This is just a compilation of the following with minor additions, so not much credits go to me, you can always check the originals. Still it's all in one place.
Bring Down the Sky DLC
Pinnacle Station DLC
1)install Mass Effect, can be found anywhere
2)install me_101a+BDtS, it's 1.01 patch + BDtS addon
3)install me_1.02 patch
4)copy DLC_Vegas folder to game\\DLC, right near the DLC_UNC folder, which is
BDtS DLC and should be there already. autoload.ini is fixed, so it should work, if not - see links above. This won't work with 1.00 mind you, so install at least one patch.
5)copy MassEffect.exe to game\\Binaries
6)enjoy the game! Run with MassEffectLauncher->play, if you try to run MassEffect.exe, it'll ask you to reinstall, which is pointless since you already applied the crack with 5)
7)if you don't want to see those unskippable logos all the time,copy all three .bik files from remove_logo folder to game\\BioGame\\CookedPC\\Movies. These are just blanks, so you can do that yourself once you find the right ones to replace.