"Most Gays are smart enough to know that the official church cannot PROVE scientifically, medically, or psychologically that either Gays or their actions are disordered."

Maybe.  But then most pedophiles are smart enough to "know" the same thing.

You say, "The church continues to use the Bible as the basis [and then any church teaching supposedly based on the Bible] as the main proof for the church's argument against homosexual acts."  

Wrong.  Read a bit on what "intrinsically disordered" means.  

You obviously have surrendered to a defining myth of our age, i.e., that nothing is knowable unless scientifically provable.  But not all truths are scientifically provable.  Prove scientifically, for example, that murder, racial discrimination, and rape are wrong.  You can't do it.  It is thus absurd to demand scientific proof of moral truths.  It is not the Church who is the fool.