Good that you are nailing it down.
I have ujam products as a replacement for the Steinberg/Wizoo virtual players, but have not used them much, and probably would not use them live.
Sample wise, my heavy hitters are Omnisphere and Kontakt, but have had no issues like yours, as they tend to load samples when needed (probably with some initial pre-loading)
Well, I have the EW Pop Brass and Soundpaint with some winds, and even them are sample-based, and they both were barely usable in my system, with the further cons that I cannot resell my licenses 
I must put a note over my keyboard: don’t buy sample-based stuff, don’t buy sample-based stuff, don’t buy sample-based stuff
Here is the casting out nines
Using Silk 1 and some other plugins, all is fine
And here is a typical set of mine to jam on a soul vibe: even better because a removed Silk 1 so gaining 1 GB
with this set, I have no more crashes in Ableton
I suspect it will be the same with Cantabile
I’ll let you know
Here it is: way better for my RAM than Ableton Live!
A typical set of mine to jam on:
Scaler 1 feeds the lower keyboard of VB3, while Scaler 2 feeds my solo notes to the upper keyboard
Broomstick Bass follows without even asking for a beer 
And a modeled guitar or one UJAM v1 adds rhythm
Still 10GB available!
Now I’ve only to hope that the next Scaler will fix the status export issue
Great… glad you found a solution.
