Is Natural Causation Existence-Conferring?

Bill Vallicella writes here: 

I hope my friend Peter will agree to at least the following:  if we adopt a regularity theory of causation, then natural causation is not existence-conferring.  The regularity theory can be stated as follows:

RT. x (directly) causes y =df (i) x and y are spatiotemporally contiguous; (ii) x
occurs earlier than y; (iii) x and y are subsumed under event types X and Y that
are related by the de facto empirical generalization that all events of type X are followed by events of type Y.

If this is what causation is, it is is not existentially productive: the cause does not produce, bring about, bring into existence the effect.  On the contrary, the holding of the causal relation presupposes the existence of the cause-event and the effect-event.  It follows that causation as understood on (RT) merely orders already existent events and cannot account for the very existence of these events.  Since Peter is a B-theorist about time, he should be comfortable with the notion that the universe is a four-dimensional space-time manifold the states or events of which are all tenselessly existent logically in advance of any ordering by whatever the exact relation is that is the causal relation.

I agree with Peter Lupu in a comment that Bill is slipping back and forth between tensed and untensed senses of existent here.   And I can't make sense of the underlined part of that last sentence.  But maybe Bill is being succinct and we should follow up his recommendations for further reading.

What Bill seems to want us to accept is the thought that if x causes y under the above regularity definition of the causes relation, then x does not confer existence on (ie, bring about) y.  Is this right?  I agree that without additional premises it does not logically follow that x brings about y.  But can't the causes relation and the brings about relation have the same extension?

UPDATE: Friday 2 August

Bill responds to my comment and agrees that causes and brings about would share extensions.   He asks how we would define brings about.  This is tricky.  I guess I'd have to say that we would declare that x brings about y in just those cases where we could tell a 'physics story' that explains y in terms of x.  For example,  we might explain the warming effect on box B of placing hot object A in it in terms of the motion of hypothetical microscopic parts of A and B---the standard kinetic theory of heat in other words.   That box C also warms up though it doesn't contain A is explained by its being left out in the sun.  That these explanations involve microscopic entities goes some way towards accounting for the invisibility of productive causation that Bill notes.

However, this account is open to the objection that the same issues concerning causation reappear at the microscopic level.  Surely we now have micro-events causing micro-events, so do we adopt a regularity or a productive theory at this level?

UPDATE: Saturday 3 August

We can go some way towards answering the above objection if we note that at the microscopic level of description we can no longer identify pairs of events that might qualify as causally related.  Rather, the description is in terms of singleton events----energy and momentum conserving collisions between pairs of particles.  We might say that the familiar causal notions do not extend down to the microscopic world.  Alternatively, that causation is an effective but approximate account of physical relations applicable only to macroscopic ensembles  of particles and their processes.