It is easy to delete old version of creo files. There is different ways you can do it:
- From Creo on current file
http://www.ptc.com/cs/help/creo_hc/creo20_hc/index.jspx?
- Use purge from commandline on all files in a folder. You can use this for scripting.
https://www.ptc.com/appserver/cs/view/solution.jsp?n=CS34721
- Use a purge tool that will add a menu RMB in windows explorer
There are tools you can download for free.
ex:
- Utlities
- Creo Purge