ok that didn’t actually work as there was no ARA SA being loaded.
i found that the vst3 plug that i left was 2k or so and the one in the bin 1.6mb…
seems that the vst3 plug has a contents package that has another vst3 plug within.
put it back and still no ARA. So re-installed the last download for the 6th time or so and so far so good. Have opened nuendo 5 times or so and no issues yet.
seems like it may have been the “defaults” needing clearing up and perhaps some corruption happening in places, requiring a further install.
fingers crossed but optimistic