Well... not all bugs can be removed via software.
Spybot is an indispensable tool, but any software is only as good as the data it receives from other sources.
It is almost impossible to keep up completely.
Human analysts run across "suspicious" files, and upload them to specialists for evaluation.
I suggest you follow the Prework instructions in my sig-- and post your logs in the
HJT thread. I think you may still have an infection.