I'm running Cyanogenmod 7 and it works fine on there as well.
From the .zip file you download (Biosboot.zip), extract the contents, go into the system folder, go into the media folder, and you should see bootanimation.zip.
Take that file and put it on the root of your MicroSD card.
Open the terminal emulator.
You'll need root access to execute the necessary commands:
mv /system/media/bootanimation.zip /system/media/bootanimation.zip.bak
cp /mnt/emmc/bootanimation.zip /system/media/bootanimation.zip
Note:the second line is NOT required, but I wanted to backup the default Cyanogenmod7 boot animation in case I ever decide to revert back.