Kashflow at the moment only allows you to record a corporation tax payment only (https://www.kashflow.com/support/kb/corporation-tax-2/) but no way of creating the initial liability (i.e. the amount due). So when you create the payment bank transaction and run the balance sheet the payment shows up as an asset when really the payment should have cancelled out the liability (i.e. the bill from the HMRC).
For me, this is an omission of basic functionality as there is no way of balancing the payment against an initial liability. Please fix.