SYMPTOMS:
Poor performance on Intel Macs.

RESOLUTION:
There are a couple of things that ight improve the games performance until we get a patch released.

Try these:
-Try downloading the OS 10.4.7 Combo patch from Apples website:
http://www.apple.com/support/downloads/macosxupdate1047combointel.html
-Try launching the game in "windowed" mode. This seems to work well if the user is experiencing kernel panic related crashes.
To do so, hold down the "apple" key while launching the game. Then, select the option to play the game in "windowed" mode.

These are the settings in-game you can change to get the most out of your system:

Lowest Resolution: 1024x768
Anti-Aliasing Multisamples: 0
Graphics Quality: Low, turning the graphics quality to low should set these as follows:
Render Quality: Low
Globe Quality: Low
Animations Frozen: on
Single Unit Graphics: on
Effects Disabled: on
Globe View Buildings Disabled: on
Low Resolution Textures: on
No Movies: on
If all else fails, you may try turning off all sound effects.

Outside of the game, if you wish, you may edit the configuration file found at Documents > Civilization IV > CivilizationIV.ini
You may try to tweak the settings more to squeeze a little bit more performance out of your system.

General performance-related options:
MinimapTrilinearFilter = 1 change to 0
HideMovieBackground = 0 change to 1
SyncInput = 0 make sure it's 0

Quicker start ups. These shouldn't affect in-game performance but should hopefully help the game start up faster:
DisableCaching = 0 make sure it's 0
NoIntroMovie = 0

Debug options. These should be off by default but couldn't hurt to double check :
LoggingEnabled = 0
SynchLog = 0
RandLog = 0
MessageLog = 0

Hopefully, using these guidelines, you may adjust your game to run optimally on your machine. Thank you for playing Civilization 4!