So what is new versus already extant in the Cymbals part of this?

I see there is a Crashes ensemble, a big and small metals, which resemble the things in BBO I have.
Are these the same? All that was new in the Orchestral part of this was the Latin percussion and some birdcalls and whistles. I see there is a Sabian piatti, a sizzle cymbal and two splashes I don't have and probably the finger cymbals are new.

Donno, look for walkthroughs at Youtube.
IME the close mics with no Room Mix or Mains or Surround activated is just about dry as a bone.

the Synch'd WW have things the VI doesn't at all and likely is missing some things. It's two different products. 

the way I approach this is with MIR Pro 24, so I run out of slots there but having many Synchron Player libraries mixes quite well with Synchron in MIR, with also the option of MIRacle or one of the enhancements of Hybrid Reverb. In fact the Synchron products have an enveloping quality in the surround or surround-to-stereo that MIR doesn't, so for me best ot two worlds.

half tempo, though, far too extreme for the time stretch on most trills methinks, it'll likely sound horrible. 

I did a 120BPM to like 107 there and it's already getting drastic

The speeds are what was sampled, it's not LFO (artificial) vibrato to assign to a controller at all.

You could stretch it to half tempo if you stick to the Room Mix patches or the MIR Unprocessed. The only control of this will be to CC crossfade from a cell to the next one, in the tree structure with a time-stretched same cell below the 'regular'.

looks like this (open screen vid in new window/tab): xfade trill speed

Agreed, first order of business is the plugin, one may simply use slaves for the samples, being able to instantiate VEP on the host machine is only truly needed if the local host is all there is.

the latency is determined in the DAW or sequencing host, period.

if it is solved by higher buffers, that's that.

Well, as to SINE it can't be a universal issue, I have several instances of it in every project for a while and it looks as snappily as anything does here. They're not gigantic instances of 100 articulations or anything. but in itself it loads fast, off of an external SSD.

What I do is go to an extant Synchron, to Control and right-click directly below the name & copy and paste it to a new instance. if there's nothing instantiated it's quicker to just load one of my user presets and do than change all of it.

sometimes there are variances in the Dimension controller but in general I have consistency.

Also the BBO libs here so far do default to CC1 for veloXF. something like Synch. Strings pro are the old paradigm from VI, CC2.

My preference whenever available is surround-to-stereo, I don't have a surround configuration installed.

I stand corrected! thank you, I never saw that before

(C0 is what Yamaha calls MIDI Note 24, Roland calls it C1 since the outset of MIDI; VSL uses the latter by default)

bottom of the image; and those will begin at left with C0 aka C1, MIDI note 24

Apparently the Matrix Level 1 combined articulations is set to CC1, for some reason.

no problem: 

Particular DAWs also have the limitation; eg., REAPER does not, it does not make the distinction effect to instrument channel. I don't use it but this is a selling point for fans of it.

In Cubase an effect may be approached to effect this by a kind of back door using VST3 sidechain input if the plugin has that. I saw someone trying it in Studio One to no avail with a granular effect which can use note-ons but the version of it was not VST3, for instance, it's identical to Cubase's handling.

I have only the one anecdote, but I did purchase and use a refurbished MacPro a while back, it was not distinguishable from a new computer AFAIC.

the effect instance does not deny MIDI per se, but it is not made to enter note-ons particularly

I have definitely controlled an effect via MIDI CC in the piano roll, same channel is a limitation unless you use channel = All, having dedicated one port to it. should work, unlike the above I have not done

the instrument channel is not built to input audio at all.

you have to instantiate whatever it is as an effect.

this is true per se, on either platform, any version

This has occurred numerous times over years now. I tend to doubt it's particular to this installation, because it's appeared on every installation I've had for a long time. More of a straight report than a request for help tbh.

When there is a switch in the matrix by KS and a KS to a cell in the dimensions at the same time, the cell switch variously fails (not 100%, somewhat consistently but it could get it right some of the time), either to switch at all, or last night switching to the wrong key. Not always the same wrong key, more often than not has been consistent, but close the VI channel and come back it may be a different mistake. EDIT: it is not 'in every case', but it happens frequently enough to be maddening.

Happens on render as well. Placing the switch earlier is not a solution as far as I can determine, and not always viable anyway. 
Latency settings do not appear to be particulary meaningful here either. Right now I do 192 samples which my audio interface assesses as round-trip 8.5ms. But same thing on a much less robust machine with 512 or more, and/or with no audio interface, etc.

This is in VE Pro 7, VI Pro both most recent version. It may be more prevalent in larger projects but I wouldn't be confident to assert that as a fact. Chances seem higher that if there is double switching _and_ a vertical dimension switch by CC that it will fail, but I cant show that statistically without being very methodical, and it doesn't seem it would be too fruitful to embark on that mission either. I was looking at a pretty involved preset it would be a problem to reconstruct say inside a single matrix to work around it, but I isolated it to a specific change I could and did effect.

An instrument library is going to need a license for every distinct instantiation, computer-wise. The names in the elicenser application are quite specific, and in the case of a library with a standard and a full version this too will be apparent.

I think at this point it's only going to change in projects like this with better cores distribution, because in isolation/the standalone it doesn't occur. It's fighting and losing a battle with other things in a VE Pro project with reasonably playable latency. Def significantly more frequent an occurrence here with duplicated channels of one mic each, or the mics selection has no impact really; the overload factor is multiplied.

Well, for me "8th notes" is too imprecise to have much of a thought about. Durations could vary quite a lot for that. If you mostly mean a note which pretty much takes up the entire duration you aren't going to want a super-short or staccatissimo articulation, but detache may have a too-soft or too-slow attack. It's very specific, contextual and there may be more than one answer; and in general I'd advise to expect to pay a lot of attention to articulation and embrace frequent changes.

Well, VSL doesn't run Syncrosoft so they can't really know. Yahama/Steinberg owns it and I wouldn't assume they're going to indefinitely.maintain servers for it after abandoning it.

In your position I would download a trial of current VEP or if possible VEP6 to see if it's simply VEP5 isn't cutting it with the OS version. Then, if not, a trial of a more current Vienna Instruments.