Can you explain? What is NFP? And what do they deny of EENS?

You didn’t answer the question.  They asked what is NFP AND EENS?

They promote the exact same version of NFP as the novus ordo.  That a married couple can use nfp, specifically having only marital relations on safe days, and avoiding on unsafe days, and a couple can use this for almost any reason.  Too poor, too many kids already, etc.  By purposefully only having relations on safe days, there is a 99.98% chance of not conceiving a child, it is just as anti life as the pill or condom.  You get to have your fun without children....that is no different then the pill.  
They deny EENS, namely that non catholics, who don't ever convert, can be saved by invincible ignorance or baptism of desire.  Two terms that were never intended to include non catholics.  Multiple cmri priests say that a Jєω who rejects Christ can be saved, in his state.  The say they believe in EENS, but then deny it repeatedly through modernist double talk.  

Lefebvre taught the same. As for NFP, even pre-V2 Popes have taught that. Not saying either are right - but it's a bit hypocritical to condemn CMRI for positions which, in the former, other Trads and, in the latter, pre-V2 Popes also held.

This whole Pius XII being an antipope nonsense is honestly a pretty good reductio ad absurdum of Sedevacantism.  I'm usually sympathetic to Sedes, but I think the epistemic basis on which the whole thing is based is extremely problematic.

I do not by any means claim to be an expert on theology, but it seems way more reasonable to me to just believe that some encyclicals, between Vatican I and Vatican II, exaggerated the prerogatives of the Pope.  This isn't necessarily malicious.  Sometimes children do indeed have to disobey their earthly fathers, however, a good father is not likely to go into all the nuances of when a child is allowed to disobey, because that would be counterproductive and undermines the authority of a parent in normal times.  And I kind of think that's what happened, particularly, with popes Pius IX through Pius XII.  When I read through Sede arguments against "R + R", its occasionally a couple quotes from earlier popes or church fathers, but usually mostly quotes between Vatican I and Vatican II.  And I'm just not convinced there can't be widely held mistakes or errors during *one* period of church history.  The whole, taken together, is infallible, but not just one part (exempting ecunemical councils and ex cathedra pronouncements of course.)

Admittedly my thinking here likely comes down to how I became Catholic in the first place.  Ultimately it was because I read the early church fathers, and concluded one, that they weren't remotely Protestant, and two, that there is a predominant teaching that we have to stay in communion with the Bishop of Rome and obey his teaching.  And, of course, the whole epistemic problem of "what makes a council" in Eastern Orthodoxy that Forlorn has pointed out multiple times here.  But I guess, in the end, its the first millennium that made me Catholic, not the post Vatican I era (and I do accept the minimal definition that Vatican I actually gives us), and I don't see the period between Vatican I and Vatican II as being in and of itself infallible.

OK I derailed this thread :D