Which Theme File did you download and install???
Did you already have CM6-RC1 installed and stable??
I installed 928DroidBlackGlass2-2-CM6-RC1-CLEARb-update.zip. Yes, CM6-RC1 installed and stable.
I also did a complete wipe and install a fresh copy of CM6-RC1 from rom manager. Installed the correct file and still get the boot animation. Actually its not even looping. Its tries to start the fire works but only shows a part of the graphics like its trying to load. Hope this helps ya bruh.
The funny thing is when CM6 first droped, and the first day you had this theme for it, I installed and it worked with no problems. But I went back and wiped everything for a fresh CM6 install(I've just been overlapping roms since FROYO release) and this is what i ran into. No matter which way i install it, Clockwork nor SPR. Update.zip nor Install from SD card.
Problem fixed. I took a look in the System\App folder and the Luancher2.apk is missing. When you install CM6-RC1 from Rom Manager you have the option to use Launcher2 instead of ADW. The file "928DroidBlackGlass2-2-CM6-RC1-CLEARb-update.zip" is missing the Launcher2.apk. Here is what I did to get the to work, also launcher2 will not be themed though :-(
1.Install CM6-RC1 normally with ADW.
2.Install 928DroidBlackGlass2-2-CM6-RC1-CLEARb-update.zip with RM.
3.Download CM6 through rom manager and choose Launcher2 this time. Wait for it to download BUT DO NOT INSTALL IT ONCE ITS COMPLETE. Is is very important not to install it or you'll wipe over the 928 theme altogether.
4.Goto "Install from SD Card in Rom Manager and browse to this directory \clockworkmod\download\
www.clockworkmod.com\download\common and install this file "Launcher2-CM6-v1.zip".
5.Reboot and let install. That should be it.
Remember the home screen for Launcher will not be themed until we have the themed Launcher2.apk available.