Actual Infinity in Reality?

[GrandizerII]

It's similar to the Watchmaker argument. He's extending what applies to things in this universe to the universe itself.

I don't see that in the argument.  The fallacy of compositions would be, that because the things that make up the collection have this property, that that which they compose must have the same property.  For example, a tooth pick is relatively weak, there fore, your bridge made out of many toothpicks is equally weak.  

What is being done here, as far as I can tell, is making a statement about all physical things.   Which if the universe is a physical thing (or collection of things), then it would apply.  You are free to argue with the reasoning behind it.  You can offer arguments against it.   However I believe you hastily and wrongly dismiss it; with the fallacy of composition.

What special reason, would we not apply this reasoning to all other physical things, but not to the universe, if it is a physical thing?

Don't be silly. By your argument, even the example you provided is not an example of a composition fallacy.