I compressed my Win8 x64 registry with your Registry Compressor, but shortly after(1 hour) the reboot my laptop BSOD'd(Critical_Process_Died).  After booting from the BSOD, Win8 notified me that my Crucial M4 filesystem needed to be repaired.  So I rebooted so Win8 could scan and repair the SSD.  After the repair I found missing icons(ironically from another Tweaking.com program I haven't used yet), errors in event viewer and I don't know what else yet.  The disk had no issues before compressing but now I see retired blocks in the event viewer.  Is the damage already done?  Should I restore .old hives?
I already ran sfc\scannow; found no problems.