I use CS all the time on Panther, no problems...

Photoshop Crashes
 

I was having a similar problem with the G5 Dual processor macs in my network. There is a Dual Porcessor Plugin update, you may want to look at that if you are on a DP machine.

Photoshop failing to load and crashing
 

After a lot of digging, I found the cause of the problem not to be Prefs, but the TWAIN plug-in : According to Adobe themselves the fix is as follows... and this applies to all PS's not just CS2/3


* On Mac OS X:
1. Go to Applications/Photoshop CS2 /Plug-Ins/Import/Export (Photoshop CS2) or Applications/Adobe Photoshop CS3/Plug-Ins/Import/Export (Photoshop CS3) and highlight the Twain.plug-in to rename it.
2. Add a tilde (~) in front of the name to disable it, or drag the plug-in to the desktop.
* On Windows:
1. Go to Program Files\Adobe\Adobe Photoshop CS2\Plug-Ins\Import-Export (Photoshop CS2), or Program Files\Adobe\Adobe Photoshop CS3\Plug-Ins\Import-Export (Photoshop CS3).
2. Right-click the Twain_32.8BA file and choose Rename.
3. Add a tilde (~) in front of the name and press Enter.

Disable the Twain plug-in for Photoshop Elements 4.0 or 5.0.

Hope this solves a few headaches out there.

Asmat you are a life saver! I have spent the last few days trying to figure this out. I previously had CS3 installed and runnning with no problems but wanted to tidy up my applications folder and found out that the only way to move any of the CS3 apps was to uninstall and then re-install them. I did this and could never get Photoshop to work again!

I was sure that I wasn't going to find any help in this thread considering all the posts were from 2004! Thanks for the info!!!