Is there an official site online where one can commence proceedings to collect an unpaid business debt? Or, years ago, i used a site whereby you could complete online and print off a court summons without actually starting proceedings. Once my bad debtors had sight of this threat it was enough to get payment however i can no longer find that site.
We used to go to the HMCS web site where you can print off a Claim Form. You can fill it in on your computer then print it off and send it to your local court with the appropriate fee and your debtor.
I'm not sure what lengths you've gone to so far to recover the debt but when I had the same problem recently with two companies I made phone calls stating our accountant was in the process of instructing a solicitor. This worked for one and got a cheque a few days later. It didn't work for the other company but me showing up at their premises did. I walked out with a cheque. Maybe you could try this.