You are welcome. As about negative height, when you should make something work, I suggest the 'stay simple' principle: start trying with 'fail-proof' parameters and then, when it works a bit, began to change.. :)
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler. -- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong. -- Iain Clarke
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