Please notice the shift in language. You went from 'everything has a cause' to 'everything that is created, is created by an intelligence'.<quoted text>
No one is arguing that "everything" is created by intelligence.
What is being argued that all things that are created, were created by intelligence.
God is eternal, so is not a part of the creation.
The first, obvious problem is that you have to show that 'being caused' and 'being created' are the same thing. But this is clearly wrong. An ice crystal can be caused by a decrease in temperature, but that crystal need not be 'created by an intelligence'. For example, it can form outside when the temperature drops.
But even your second claim (that everything created is created by an intelligence) is clearly wrong. Consider an ant colony. It was clearly created by those ants, but ant are not typically said to have intelligence. In fact, the creation of the ant colony is an instinctual act, not an intelligent one. The same can be said for spider webs, for example.
Finally, even if your (faulty) assumption that all created things are created by intelligences, to get your argument off the ground you still need to show those intelligences are created. Otherwise, your regression stops with human creators.