Open a D project with one or more files and CB starts eating 100% cpu time.
It then is extremely slow to respond to input generally and
large dialogs such as Settings->Editor taking over 2 minutes to open.
This doesn't happen if there are no files in the project and closing the project
puts things back to normal.
If you could post the project somewhere and file a bug on BerliOS, that might help fixing.
Also, can you try disabling the code completion plugin before that project?