@cougardod: A good point - I've neglected properly looking at the install / update process, but the Install Shield LE edition should allow me to manage that much better. Will add that to the list in a sec.
@nichg: You can't add nodes quite yet I'm afraid - that's on my todo list still. However, all nodes are imported from Assimp import I believe, so you can actually do that in an external editor. I want to make sure the node editing is 'safe' (you can't break the tree), so I will probably do the following...
1. Add an add/delete/import node option.
2. Make the 'parent node' field a dropdown.
3. If you try to delete a node with children, you will have the choice to cancel or move all children to the root node.
That should allow for full data consistency.
@Komag: You are correct

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Will add latest suggestions to the first post, either in a minute (if my ipad doesn't make that difficult) or tomorrow morning! Am tucked up in bed now playing the 'man flu' card with the wife to get ice cream and mugs of tea!