The SFU Kzintis are different from the Known Space/
Slaver Weapon Kzinti in part due to licensing issues.
There are discussions in various
Prime Directive volumes about the mysteries of species seeding in the Alpha Octant, as well as the issue of near-duplicate planets and other mysteries which may never be resolved. But whatever the answers may be, they would be required by the terms of ADB's licences with Paramount/CBS, the Niven estate, and the Franz Joseph estate to be distinct from non-licensed works published in other franchises.
The warp scale used in the Star Fleet Universe is talked about
in this file, which is an extract from
GURPS Prime Directive 4th Edition. (To be clear, there haven't been four editions of
GURPS PD; the tagline is more an indicator that the current version is written with
GURPS 4e in mind.)
One conceit in the SFU is that the Milky Way galaxy is physically bigger than what we know "our" galaxy to be. Each hex on the
Federation and Empire map (or rather, its "
West" and "
East" map portions; you can buy a combined large scale hex map as a special order from ADB) is approximately 500 parsecs across. This allows the habitable region of the galaxy to be one hex thick, which makes life easier when playing the strategic-level
Federation and Empire wargame.
As for the size and layout of the galaxy itself, the SFU incarnation (which was originally derived from the layout presented in the
Star Fleet Technical Manual) looks like
this. Rather than the quadrant system used in the Franchise, the SFU Milky Way is divided into 24 sectors, which are bunched into five habitable regions by near-impassable Voids, the limits imposed by the galactic energy barrier, and the Storm Zone to coreward.
The area covered by the
Federation and Empire map is shown on the galaxy map. The Federation covers much of the Beta Sector (in the Alpha Octant), the Klingons and others are in the Gamma Sector, and so on. For most of the "modern" SFU history, the Alpha Octant empires were limited to their own region of space. But due to the need to counter an invasion by the extra-galactic
Andromedans, the "home" powers would come into contact with more distant regions late in the SFU timeline.
Before launching their assault on the Alpha Octant, the Andromedans arrived in (and gradually conquered) the Lesser Magellanic Cloud, using it as a springboard for their wider galactic invasions. In order to put a stop to this, the surviving Alpha Octant powers launched Operation Unity, which destroyed the chains of Andro bases connecting the Alpha Octant to the LMC. Once in the Cloud, the Unity powers destroyed the Andro starbase providing a "trunk line" connection to the Andromeda Galaxy, and made contact with the surviving Magellanic holdouts (which had been driven into exile by the initial Andromedan conquest of the Cloud).
Over time, the LMC would itself become a jump-off point for further explorations of the galaxy. One example of this is the Star Fleet advanced technology survey cruiser
NCC-1821 USS Sakharov. This ship set out from the LMC in Y212 to visit the Omega Octant, which it first reached in Y214. It would eventually return to the Federation in Y219, providing Star Fleet with a wealth of data gathered from that volatile region of the galaxy.
It won't all be plain sailing for the Federation and others post-Unity, however. It seems that the Xorkaelian Empire (the masters of that giant chunk of space over on the far side of the galaxy) are set to launch an assault on the Alpha Octant in Y210. In their case, it has been suggested that they get across by skimming the outer edge of the Storm Zone, but the full details of that invasion won't be revealed until
SFB Module X2 is published (or perhaps not even then, depending on whether there will be a separate Xorkaelian module afterwards).
Since the Triangulum material available for
SFB is still in playtest (as in, there has yet to be a formally-published module for M33), it hasn't been spelled out just yet how the data on Triangulum appears in the "Air Force data tapes". For now, we (the readers) know some of what exists out there, but we don't yet know when, how, or even if Star Fleet manages to find out any of that data "in-universe" prior to the cut-off point in Y225.
(The Alpha timeline stops in Y225, at the end of the second generation of advanced technology. As the history file states, "Presumably a third generation of X-ships was developed, but The Next Generation is not within the scope of the Star Fleet Universe.")