I'm having installation problems too. I have the vanilla edition of Civ 4, warlords, and BtS ... but BtS won't install. Everyone else seems to be getting an "aborting installation error" but all I get is a CTD.
During installation, it will get up to the point where it says, "There is a newer version of Sid Meier's Civ 4, installing patch now." The computer works for about 2 minutes, then the hard drive light stops flashing and the entire program just disappears. No errors, no beeps, nothing. It just crashes out of existence.
I've tried just installing the programs with no patches. I've tried installing 1.74 after installing everything else. I've tried installing 1.74 before I install Warlords. I've tried installing 1.61 but not 1.74 before and after installing Warlords. I tried patching Warlords before BtS but I just get the standard "sorry, but you don't have the game installed" error message, so I gave up on that.
In other words, I get the crash during installation regardless of which patch I use or in what order I install them in.
I'm beginning to think I just wasted $30. Anyone want a copy of BtS?