Sorry, that top link isn’t the right one, but might give some more context. Trying to find the link I found a minute ago 
Edit; actually it is the right link, I just thought nminchin was the OP, I know he was working on similar.
Time for a coffee.
Sorry, that top link isn’t the right one, but might give some more context. Trying to find the link I found a minute ago
Edit; actually it is the right link, I just thought nminchin was the OP, I know he was working on similar.
Time for a coffee.