(1) God exists in the understanding, but not in reality.

Or

(1) A being than which none greater can be imagined exists in the understanding, but not in reality. — Agustino

I'd say both sentences use the same word; 'exist', but the word has a different meaning.

I can say 'dreams exist', or 'this concept exists' etc. or 'Harry Potter exists' and we understand the meaning of 'exist' by what it refers to. That meaning is different to 'London exists'. If there is a confusion over what is meant, we can ask. 'You say Harry Potter exists?' and get the reply 'I meant he is a fictional character'.

So I do not say why the idea that something 'exists in the understanding' is connected to the quite different claim that something 'exists in reality'.

So I do not say why the idea that something 'exists in the understanding' is connected to the quite different claim that something 'exists in reality'. — Londoner

In other word's the thread is as valid were you to call it "Ontological Argument Proving Harry Potter's Existence"

In proportion to Nothing (the starting phase of the Universe), a thought or a basic sense like "the will of existence" would be Everything.

Such a simple consciousness could be called God.

Everything is relative to the space and time of the observation.

So my understanding of the ontological argument is that God is the greatest thing that we can think of. Things can exist only in our imaginations, or they can also exist in reality. Things that exist in reality are always better than things that exist only in our imaginations. If God existed only in our imaginations, he wouldn’t be the greatest thing that we can think of, because God in reality would be better. Therefore, God must exist in reality. This argument can be summarized as:
1. God is a being than which none greater can be imagined (the greatest possible being that can be imagined).
2. God exists as an idea in the mind.
3. A being that exists as an idea in the mind and in reality is greater than a being that exists only as an idea in the mind.
4. Thus, if God exists only as an idea in the mind, then we can imagine something that is greater than God.
5. But we cannot imagine something that is greater than God.
6. Therefore, God exists.
I know that one of the most well known objections to this argument is Gaunilo’s “The Lost Island” argument that uses the same structure as Anselm’s Ontological argument to prove the existence of the greatest island. But I am more convinced by another objection that I found more interesting by Immanuel Kant. According to Kant, existence is not a predicate. An example of what he says is that if a triangle exists, it necessarily has three sides. But it could be that no triangle exists at all. Because the idea of existence isn’t part of how we define a triangle. If God exists, then he must be the greatest being we can imagine. But that does not mean that he does exist. Predicates add to the essence of their subjects, but they can’t be used to prove their existence. Kant believed that the ontological argument was flawed and any argument for the existence of God based on the proposition that a God exists in reality is greater than a God that only in the imagination is based on confusion.

I agree with you on the fact that the ontological argument has many flaws. As many of its arguments are based on the logic whereas humans prefer some observation to strengthen the outcome of deduction. Thus, I believe Stenger's objection to the ontological argument works as well because empiricism plays a big role in our daily lives and explore new knowledge and inventions.

He provides his objection in this form:
(1) If the ontological argument is sound, then you could know that it's sound without making any observations
(2) you would never know that any argument is sound without making any observations
(3) thus, the ontological argument cannot be sound

The Greatest Conceivable Being cannot just exist in our minds only but in reality as well. However, we cannot double this statement as there is no empiricism for the Greatest Conceivable Being other than the accounts of "miracle witnesses", especially when we observe the big problem of evil.

Anselmian onto/logicing:

1. Dracula is the most dangerous conceivable vampire (our definition)
2. a real vampire is more dangerous than a fictional vampire (trivially true)
3. if Dracula was not real, then a more dangerous vampire was conceivable (which would contradict 1)
4. therefore Dracula is real (from the above)

Or maybe:

1. define Vlad as the most "vampirish" being
2. a fictional being cannot bite and turn me, a real being can
3. for Vlad to be the most "vampirish" being, Vlad must be able to bite and turn me
4. therefore Vlad is the real deal, since otherwise 1 is contradicted

Should we be concerned...? Or not...?

I'd like to critique your argument, specifically the premise that reality is always better than the imagination, and that therefore God must exist in reality, and also the premise that God is the greatest thing we can think of.

You claim, "Things that exist in reality are always better than the things that exist in our imagination." I can see a point here that truth and reality ought to be valued, but that's not what you're directly expressing; instead, you claim that things in reality are "better" than things in the imagination. Clarification is needed: what do you mean by "better?" If you mean that reality is more concrete and authentic, then that seems fair. However, "better" can also refer to something that is more pleasant and enjoyable. In that case, reality is not necessarily better than the imagination. Things in reality can be horrific, unfair, and painful, whereas things in the imagination (daydreams, for example) can be as pleasant as one wants them to be.

Building on this, you then say, "If God existed only in our imaginations, he wouldn't be the greatest thing that we can think of, because God in reality would be better." I'm unsure as to your specific meaning here. Are you stating that it would be impossible to imagine a God who would be as great as the real God, and that we are unable to conceive of the greatness of His nature? You seem to be implying that our ability and capacity to think about God proves his existence, which is an intriguing claim, but isn't strongly presented in this argument. This claim also rests heavily on the premise that “God is the greatest thing we can think of,” which I will address next.

You put forth the premise, which is really the backbone of the above claims, "God is the greatest thing we can think of." This statement is too vague to offer any support to the rest of your argument. How are you defining greatness? To a theist, that statement might be true, but an atheist would wholeheartedly reject it, and thus dismiss the remainder of your argument.

Overall, I believe that this argument would benefit from refining the above premises to be more specific, and also giving a better definition to ideas such as the reality/imagination comparison.