There is nothing bad about booting Snow Leopard in 32-Bit mode. Even real Macs do this by default. The 32-Bit Snow Leopard Kernel doesn't mean to use 32-Bit in generell the software can adress more than 3GB of memory even using that mode.

And you do not need to enter this option manually every time.
Look into /Extra folder (if it exists) for com.apple.Boot.plist - if there is not such file go to /Library/Preferences/SystemConfiguration
Copy that file to your Desktop. Open it and look for
<key>Kernel Flags</key>
<string></string>
between the string field you can add any boot option you want to use.
Once you are done editing this file, copy it back to the folder you took it from.

Once you are on 10.6.2 you can use 64-bit Kernel again, as the Atheros drivers got translated with that update.

I bought my Retail copy for 29€ from my local Apple reseller and installed it using my already installed 10.5 Leopard system to a second partition.

Back to 1.:
Here is the mentioned Kernel Extensions, which I believe should fix this:
http://rapidshare.com/files/30969294...cyRTC.kext.zip

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