Thanks. I've done a bit of experimentation with both of your suggestions.
At first I stayed with the Legato voices and played around with Portamento (P) and Curve (C)
1st phrase was just an upward arpeggio C E G
With no overlaps, sounds OK
Add overlap between C and E, and between E and G
Legato 1 Portamento 1, Curve 1: slides up from C to nearly G as one 'note' then cuts out
Legato 2, same P and C settings, slides from C to E, then E to G then cuts out
Reduce P to 592m
Legato 1 now sounds like Legato 2 did above. Legato 2 sounds almost acceptable but still cuts out during note 3
Reduce P to 349m. No difference
Reduce P to 118m
Both Legatos sound identical - reasonable slide from C to E and E to G but cuts out halfway through G
Added overlap to second phrase, C D E F - slide sounds awful
Reduce P to 33m - sounds better but last note still cuts out halfway.
Legato 1 with P at 38m and C at 0.7 sounds reasonable.
What I've learned : In C E G, the top G only sounds its full length if (a) there's no overlap and no portamento or (b) change voice from Legato 1 or 2 to Mono so no portametno. Any P or C makes you lose half of the length of the last note.
I then looked at your second suggestion, the LFO settings. I don't have any '11 Violins' or any marked No Vib but I have a '14 violins sustain nv d LP' - no idea what most of it means but I'm guessing 'nv' means no vibrato. I can't hear any vibrato.
I changed the settings as best I could to yours - couldn't get them exactly as you can only play the dials, not type in a value. Screenshot attached.
I couldn't hear any difference when I used the Mod wheel - I'm not sure what I'm supposed to hear. So it may not be mapped right. It moves on the Miroslav UI but I don't know if it's doing anything.
Your second message really tells me I need to learn more about MIDI, in particular CC messages and LFO values, as I have no knowledge or understanding at all. I can see now that I need it in order to discuss this stuff intelligently. So I'll go and do that.
I'll come back to this when I can grasp the language a bit better. I really appreciate you taking the trouble to help with this - thanks!