On the three Kontakt instances I’ve checked, the first note played on the first activation of each rackspace is delayed ~200 ms (total SWAG… definitely noticeable, but less than a half second). I’ve tested this on three rackspaces. Two use Hammonds from the Kontakt Organs library and one is a three instrument multi with Marimba, Vibes, and Flute. Subsequent activations within the same session do not produce the delay.
Using Predictive loading, if the rackspaces are unloaded and reloaded, the delay occurs.
Windows 10 Pro
Samsung 840 SSD