I did an uninstall of version 18.104.22.168 previously, and an uninstall of 22.214.171.124 now. In both cases the uninstall did not remove the "PersonBrain" subdirectory structure. It looks like two 0 byte files (BrokenFiles.dat and pb.bin) are preventing removal of these directories.
PB 6.0 Pro
Windows 7 Pro 64-bit