Murray, a member of a group of disgruntled shareholders pushing for change, hit out at the lengthy statement released by chief executive Craig Mather on Friday night.
Mather said: "A group felt they should become directors. No plan. No investment. No vision. Just an obsession to wear a tie and sit in the directors' box."
But former Rangers director Murray admitted he was "disappointed" by the comments and stated he believed they were "unbecoming" of somebody in Mather's position. Speaking to Radio Scotland, he said: "For the chief executive of Rangers Football Club to issue that statement I think is unbecoming. We had constructive dialogue and actually had a compromise in place that was eventually blocked by [brokers] Strand Hanson.
"We are going to have an AGM in October and I would encourage every single person who has shares to go along, listen to the debate, make a balanced view, vote their shares, vote for what they want, vote for who they want on the board."
The latest verbal salvoes between the parties battling for control of the club came on the day Rangers announced Sandy Easdale, co-owner of McGill's Buses, had been appointed to the PLC board, joining his brother James, who is also a director of Rangers International Football Club plc.
Murray revealed that former PricewaterhouseCoopers executive chairman Frank Blin had walked away from negotiations after growing frustrated by the dealings with the current Rangers board.
He said: "He is a Rangers fan. He is a very successful businessman. He has been in business for 38 years. But he has been left sickened by the constantly changing positions in the negotiations we had with the board, the constant spin in the media by the various PR people Rangers have.
"We got to a position over two to three weeks where we had a compromise position where various people would be joining the board. We had that agreed last Monday.
"We were expecting to make an announcement the following morning. It was all agreed. Then, from nowhere, there was a blockage from the so-called nomad, the nominated advisor, Strand Hanson, for reasons they still haven't told us.
"One of our conditions was that there could be no guarantees on any board member, including us. Every board member would be put up for re-election at the AGM and the shareholders would vote on who they wanted. I think that is right. Then we had all these threats in the media about how he [Jack Irvine] was going to smear us in the press about our private lives and so on. We don't need this stuff. We have families and other business interests to protect. It is a veiled threat which is just to me not right."
Murray, whose Blue Knights consortium failed in a takeover bid last year, also revealed the actions of Rangers oldco administrators Duff and Phelps were being investigated by liquidators BDO.
He said: "Speak to any insolvency practitioner in the world - and BDO are looking at this very carefully - and they will tell you it is unheard of for a CVA to fail and there to be an automatic sealed contract on the sale of the assets. What happens in every case is the CVA fails, the assets are brought back to the market and are sold to the highest bidder. In that case it was Jim McColl, Douglas Park and Walter Smith."
Murray also stated he would be prepared to work with South African-based businessman Dave King if the former Rangers director was prepared to invest in the club once again.
He said: "He has the same concerns that we have about the club. He has said he will invest in the club, he just won't give any money to the existing shareholders. If the club does need [money], which we think it will do, in the next 12 months then Dave has said he would be happy to lead that investment. I would be happy to have Dave alongside me."