In the course of learning to use my chromebook I inadvertently generated a large number of entries in the 'offline' and 'recent' sections of the offline file browser, and I couldn't delete them.
Bit of a nuisance because I like to be in control.
Anyway, the good news is that after reading several forums I found there are ways to delete.
First and foremost, there is a bigger and more powerful version of the file browser online, go into the 'All Apps' area and click on the 'Google Drive' icon. This puts you in better control of what files are where.
Then, to remove files from the 'Recent' list you need to look in:
chrome://drive-internals
Under the heading 'Local Metadata' you click on 'Clear Local Data'.
Hope this helps anyone who is keen on having a clean machine.
PS - A tidy desk is a sign of a sick mind, or so I am told.