Is there any way to do a search & replace (e.g. for a changed subsystem name) in forms/tool dialogs? Yes, that is possible. You simply have to iterate over the content of a container and ask each view for the control properties and change those accordingly.
Below you find a simple module which performs this task. A source string is replaced by a new string in the link, label, guard and notifier fields.
Subsystem Omi is useful for BlackBox 1.3.x. At BlackBox 1.4 this feature exist already in menu [Layout].