The Police are wrong, if someone has forged your signature this is not a civil matter as this is fraud by false representation which is a criminal offence and they can be prosecuted for after the Police investigate. So you should go to your local Police station and make a formal statement and complaint.
If this is not a commercial unit then the other side will need a Court order to remove you from possession. Therefore you should write back to the Solicitor highlight the issues you have raised here.
In the event that proceedings are issued, you can raise a counter claim and seek a Court order that the property be transferred back to you.
You would need, if it goes to Court a handwriting expert to confirm whether the signature on the documents is likely to be yours or not.
If the expert sides with you then I would imagine that would convince a Judge to make the Order that the property is transferred to you.
But the Police is your first step as this will deal with any investigation and prosecution on your behalf.
Sorry for the overnight delay but I hope this answers your question quite fully.
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