This is more a tip rather than a question...
The "Common Editor Defaults" for Textpad (www.textpad.com) will always spawn a new instance of textpad even when the occurrences are all contained in the same file.
This is the correct setting for having texpad reuse the existing editor instance (whithout risking to end up in having edited the same file in different independent editor windows)
Program Location = C:\Program Files\TextPad 8\system\ddeopn32.exe
program Parameters = TextPad.dde $(FILEPATH)($(LINENUM))
(the ddeopn32.exe utility tool is part of the texpad installation)