There are a couple of legal issues insofar as your property is concerned.
The first would be the legality of the council's decision - I have doubts that their decision was legal due to the fact they did not follow their procedures but in relation to the aggrieved party (yourself) not having any opportunity to object to a planning application for a bar under your property, which resulted in a zero value for a mortgage.
With the Ombudsman agreeing to the fact the council failed to follow it's procedure, you have two approaches. The first would be to launch a judicial review of the council's decision. This means that a judge looks in to the legality of a decision of a public body such as a council - you would need a law firm to do this as the area of law is complex and judicial review proceedings can be expensive too - so a law firm should do this for you and to act on a no win no fee basis.
If a judge finds that the decision was illegal, they can overturn the council's decision, so this potentially has a huge impact for you in that the bar would not be able to operate and your property value would be back to normal. The other area of law is to sue for damages - if judicial review proceedings are not an option (e.g. due to expense). The claim would be for the diminution value of your property, which is likely to be substantial, so again a law firm should help with this.
I can recommend either Slater & Gordon Lawyers (tel: 0161(###) ###-#### or Irwin Mitchell Solicitors (0370 1500 100). When you ring them just say you want to speak to a solicitor as regards ***** ***** review of a council's decision and also a claim for damages in relation to the property value.
I hope this helps - if you can please accept the answer and give me a 5 star rating (there should be a button on your screen to do this), I can answer follow up Q&A's at no extra charge and Just Answer will credit me for helping you today.