Have spoke on the phone to epson, they didn't really seem to have to much of an idea, the chap i spoke to recons the 'ink level monitor' info is stored in the registry, and that ccleaner is probably deleting this.
This I find hard to believe, correct me if I'm wrong but ccleaner doesn't remove or delete registry entries unless i'm using the 'issues' scanning option.
I'm going to experiment and tick on and off the different types of system files that ccleaner scans and deletes to find out wot type of file my epson printer is using to store it's ink level data.
and maybe I'll just have to leave that particular box unticked.
Thanx Marc0nius