This quote you provided from UDG further makes my case:

77. I decree that the dispositions concerning everything that precedes the election of the Roman Pontiff and the carrying out of the election itself must be observed in full, even if the vacancy of the Apostolic See should occur as a result of the resignation of the Supreme Pontiff….

It states that "dispositions concerning everything that precedes the election" (which includes death, funeral, and burial of the previous Pontiff) "must be observed in full." And these "dispositions" must be "observed in full" even if the "vacancy of the Apostolic See" occurs "as a result of the resignation of the Supreme Pontiff."

This means that the Supreme Pontiff can "resign" but a resignation does not abrogate the required "dispositions." Again, these "dispositions" include the funeral mass and burial of the previous Pope.

The case where the Pope has resigned but it not yet dead is dealt with in the first few sections of UDG:

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1. During the vacancy of the Apostolic See, the College of Cardinals has no power or jurisdiction in matters which pertain to the Supreme Pontiff during his lifetime or in the exercise of his office; such matters are to be reserved completely and exclusively to the future Pope. I therefore declare null and void any act of power or jurisdiction pertaining to the Roman Pontiff during his lifetime or in the exercise of his office which the College of Cardinals might see fit to exercise, beyond the limits expressly permitted in this Constitution.

2. During the vacancy of the Apostolic See, the government of the Church is entrusted to the College of Cardinals solely for the dispatch of ordinary business and of matters which cannot be postponed (cf. No. 6), and for the preparation of everything necessary for the election of the new Pope. This task must be carried out in the ways and within the limits set down by this Constitution: consequently, those matters are to be absolutely excluded which, whether by law or by practice, come under the power of the Roman Pontiff alone or concern the norms for the election of the new Pope laid down in the present Constitution.

3. I further establish that the College of Cardinals may make no dispositions whatsoever concerning the rights of the Apostolic See and of the Roman Church, much less allow any of these rights to lapse, either directly or indirectly, even though it be to resolve disputes or to prosecute actions perpetrated against these same rights after the death or valid resignation of the Pope.12 All the Cardinals are obliged to defend these rights.

4. During the vacancy of the Apostolic See, laws issued by the Roman Pontiffs can in no way be corrected or modified, nor can anything be added or subtracted, nor a dispensation be given even from a part of them, especially with regard to the procedures governing the election of the Supreme Pontiff. Indeed, should anything be done or even attempted against this prescription, by my supreme authority I declare it null and void.

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Assuming that Benedict XVI validly resigned (which is doubtful), a vacancy of the Apostolic See does not, by itself, trigger a new papal election. The actual legal "conditions" or "dispositions" required for a new papal election are listed in UDG itself. And, as I have shown, the primary conditions for such election are the death, funeral, and burial of the previous Pope.

As Section 3 above states, in the situation where a Pope is not yet dead but has validly resigned, the "Cardinals are obliged to defend [the] rights" of "the Apostolic See." Those "rights of the Apostolic See" are spelled out in the Apostolic Constitution Pastor Bonus and in Canon Law.

But the main thing is that the College of Cardinals cannot call a conclave until the Pope is dead. If he is not dead, the functionaries of the Apostolic See (the Curia) continue to run the Church while the previous Pope is in retirement. But the Curia cannot change Church law during that period. Those officials can only carry out "ordinary business and of matters which cannot be postponed," as stated in UDG section 2, quoted above.

So, are you saying that if a pope resigns, a new pope can't be elected until he dies? 

Yes, that is what UDG says. A valid resignation of the Pontiff is not enough to trigger a new papal election. The Apostolic See is more than "the Pope."

Yes, the Apostolic See is headed by the Roman Pontiff. But the other members of the Apostolic See are the curial officials, and those curial officials do not "cease from their office" except on the "the death of the Supreme Pontiff," not upon his resignation. See this from Pastor Bonus:

Art. 6 — On the death of the Supreme Pontiff, all moderators and members of the dicasteries cease from their office. The camerlengo of the Roman Church and the major penitentiary are excepted, who expedite ordinary business and refer to the College of Cardinals those things which would have been referred to the Supreme Pontiff.

You can search Pastor Bonus for a reference to the "resignation" of the Pontiff. You will not find mention of it. That is because a papal "resignation" does not change anything regarding the curial offices of the Apostolic See. Only the "death of the Pope" changes who holds those offices.

So, Benedict XVI placed the Church in kind of suspended animation with his Declaratio. The curial officials have the power to pay the bills and keep the lights on. But they cannot change Church law. Everything that Bergoglio and is false regime has done is null and void.

If people will just read UDG and PB carefully, looking for the loopholes that I am pointing out, they will see that the loopholes do indeed exist and Benedict XVI cleverly exploited those loopholes. By doing so, he prevented Bergoglio and his henchmen from doing any damage to the legal/doctrinal aspects of the Church.

Billot's argument would make him legitimate simpliciter.  I don't agree with Billot's position, but that's a side point.  So this "irregularity" would render Jorge ineligible to make St. Malachi's prophecy, but eligible to be the pope.  Something seems off, especially given that St. Malachy included a number of Antipopes in his list.

A "canonical election" in March 2013 must have followed the law on papal elections found in the Apostolic Constitution Universi Dominici Gregis, which states:

76. Should the election take place in a way other than that prescribed in the present Constitution, or should the conditions laid down here not be observed, the election is for this very reason null and void, without any need for a declaration on the matter; consequently, it confers no right on the one elected.

Yes, that is what UDG says. A valid resignation of the Pontiff is not enough to trigger a new papal election.

Yes and no.  Even though it's disciplinary in one sense, there's a latent principle in the legislation, one that invalidates "Universal Acceptance" theory.  Pope Paul IV declared that a heretic Pope would be illegitimate even IF he were accepted "by all" and honored as pope, etc.  That would be completely moot, since the alleged theological principle (rooted in Divine Law) would trump his legislation, since Universal Acceptance would kick in and invalidate it.  At the very least, this indicates that Pope Paul IV did not believe that there was such a thing as Universal Acceptance that would legitimize and otherwise illegitimate pope.