OH Dear,
Not a lot you can do Martin, just wait for the penny in the pound from the liquidators (if you are lucky)
Sorry cant offer any advice really, but over the years have had a few customers go bust on me, Two of them actually got back on their feet and continued to buy from me, putting a few quid on each job untill they had cleared the old debt. Sometimes people do have a conscience, its not always their fault that they go skint.
there but for the grace of god…..
Peter