Penrose believes that the nature of consciousness is connected to a physical phenomenon which happens in our brains but not in computers, therefore he does not believe a computer can posses consciousness no matter what software you put on it. He's written several books on the subject as well as given a number of talks which are available on YouTube, but I don't have one link which I'd recommend above others. Sorry.
I don't think the properties of identical particles in Quantum Mechanics bring much if anything to the discussion at hand. Even if we lived in a classical universe, in which every atom would be unique and numbered, we could come up with thought experiments, in which, say, (a) a mad scientist makes an exact copy of your body including brain, (b) then kills you and feeds your ground body to your unsuspecting copy as hamburgers, and (c) all the atoms from your digested body make it to the same spots in your copy's body that they used to occupy in your own. (That last part might seem like a stretch, but really, is it more of a stretch than postulating that you and your copy would be identical in a sense you invoke in QM?) The end result from the world's point of view is exactly the same as if nothing happened to you.
And all that has not even that much to do with the question of what happens when you upload your brain to the computer, let it run for a while, and then recreate a physical brain with the updated state from the computer, since then the final state is emphatically not identical.
§2: Your argument actually doesn't feel like such a stretch. QM is just the final nail in the coffin, that made me actually comfortable with cut & paste transportation.
§3: We could actually get the same effect as the mad scientist, actually. Freeze my body, upload, lock me in a virtual cell for a few subjective hours, download by rearranging my neurons (or even my whole body) according to my virtual trip, reboot. There, you get the same final state: same atoms, and same memories compared to what they would be if you locked me in a physical cell instead.
I don't think the properties of identical particles in Quantum Mechanics bring much if anything to the discussion at hand. Even if we lived in a classical universe, in which every atom would be unique and numbered, we could come up with thought experiments, in which, say, (a) a mad scientist makes an exact copy of your body including brain, (b) then kills you and feeds your ground body to your unsuspecting copy as hamburgers, and (c) all the atoms from your digested body make it to the same spots in your copy's body that they used to occupy in your own. (That last part might seem like a stretch, but really, is it more of a stretch than postulating that you and your copy would be identical in a sense you invoke in QM?) The end result from the world's point of view is exactly the same as if nothing happened to you.
And all that has not even that much to do with the question of what happens when you upload your brain to the computer, let it run for a while, and then recreate a physical brain with the updated state from the computer, since then the final state is emphatically not identical.