At least 18 people have now come forward raising concerns over a second IT system used by the Post Office, Sky News understands.Accounting software, Capture, was installed by several post offices around the country in the mid to late 90s - before the notorious Horizon system was rolled out. Hundreds of sub-postmasters were wrongly convicted after errors in the Horizon software caused false accounting shortfalls.Lawyers for the victims of the Post Office scandal have told Sky News more people who...