Application to Set Aside or Vary Order Granting Permission for Filing Ancillary Claim – Whether Appropriate Application – Whether Applicants Should Have Filed Appeal against Order – Whether Ancillary Claim Appropriate Based on the Grounds Stated – Provision in Policy of Insurance for Arbitration – Whether Ancillary Claim Should Await Outcome of Arbitration of Issues – Subrogation – Alleged Negligence of Attorney-at-law.