It is certainly true that a purely digital model of a conscious brain could not perform any of the physical actions that a conscious person can do, such as actually move chess pieces, but the addition of actuators for such interventions in the physical world is not conceptually problematical, and clearly beside the point.
Talk of properties, without inquiring more deeply, was pilloried by Molière in a rather well-known comment:
"It is asked what the cause and reason are of opium's making one sleep.
"To which I respond: because there is in it a dormitive virtue whose nature it is to put the senses to sleep."
It also tends to give rise to positions such as a disbelief that iron ships could float, on the grounds that iron, unlike wood, lacks the buoyancy property. The generalized fallacy here lies in taking a lack of knowledge for proof that something is necessarily the case.
There is no need to feel bad about disagreeing wth Searle - he is not lacking in self-confidence, and I imagine he would laugh at the thought.
So Searle does not agree that consciousness is a product of or a form of computation, which is where he and I part ways.
If that's true then the simulation argument fails. I'm not convinced though. It seems to me that the materialist argument, and Searle seems to be a materialist, is that consciousness is an emergent property of neuronal activity which is basically a form of computation. Well simulated weather isn't weather, but computer simulated computations are actually computations.
So while I am highly skeptical of the simulation argument, I don't object to it in this respect. Also I feel bad disagreeing with Searle as I think he gets so much else right and has made many very valuable contributions.