I drove a hire car in the UK on the paperwork issued by KEP while my Greek licence was being renewed. I took a photocopy of the licence that was being renewed and a translation of the KEP document. I can't see why a photocopy of your expired licence together with the temporary licence plus a translation shouldn't work just as well.
If you are stopped by the police in the UK simply explain that your licence is in the process of being renewed, that the process is taking a long time in Greece because of an industrial dispute in the department that issues them and so they have issued you with a temporary one until the dispute is resolved. OK it isn't in the EU format but they can see from the photocopy of the original, which is in the EU format, what you are entitled to drive. The temporary licence simply extends the validity of the original. I can't guarantee it will work but you have to take some risks in life.
Got a bit more on the 74 and over driving test today. This candidate had to drive out of the car park and turn right, then right again, right again, right again back into the car park. Job done. He did say that he had to ask the examiner to fasten his seat belt though! Bob.
I thought it was illegal to wear your seat belt within the town limits? Every time I went on a long journey with any of my Greek work colleagues they wore their seat belts when on the highway but immediately unfastened them the second they drove past the sign with the town name on it. I automatically assumed they didn't want to get caught wearing it?