Thanks for the responses Pathfinder and SJ :thumbsup:.
The advice on the use of all the disperate types of armour will come in handy next game SJ ... I knew I was doing something wrong

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I was aware that the Structural Supports didn't contribute much to the overall 'armour' effect, I was just concerned that by putting them on I was somehow intefering with the ability of the advanced armour types to do their job (as I vaguely recalled reading somewhere around here that mixing up the kinds of armour caused the protection effects to become eratic).
From what you say tho', it seems I either misremembered what I'd read or that the problem has now been cured. Many thanks.