Okay, so it turns out that if one switches to Flow mode auto-population of SV's do work. It is only in Precision mode that it does not work. W 10 here.
Synchron - Woods, Brass, Perc I, Str Pro, Elite Str, Duality Str & Sordino, Prime Studio - Woods, Perc, Solo Str, Ch Str, Orch Str, App Str, Harps, Choir Studio Dim - Brass, Strings VE Pro, MIR Pro 3D, Vienna Suite Pro Cubase 14, Studio One 6, Dorico 5