Here's some debug... If it's exactly with your amendments...
TOP NODE
Group = System
Name = System
Added - myTree.Nodes.Add(, , _1_System, System, strGraphic)
CHILD NODE
Group = System
Name = Exit
Here's where it's trying to add the next node but failing
If I just include your code amendements on the child node creator...
TOP NODE
Group = System
Name = System
Added - myTree.Nodes.Add(, , System, System, strGraphic)
CHILD NODE
Group = System
Name = Exit
Added - myTree.Nodes.Add(System, tvwChild, _2_Exit, Exit, strGraphic)
CHILD NODE
Group = System
Name = Help
Added - myTree.Nodes.Add(System, tvwChild, _3_Help, Help, strGraphic)
CHILD NODE
Group = Help
Name = Help Files
It gets a little further
Don't know if this helps - I am trying to get my head around it!!!