My apologies _toralf_, of coarse I don't mind! Here you go :
copy the following code snippet into some file "diffmerge.vbs" into the PSP subfolder "script\VBScript" : Const module_name = "DiffMerge" Const module_ver = "1.00" newFilename = "" oldFilename = "" Sub setNewFile If (editorsCount = 0) Then Exit Sub End If logClear() Set editor = newEditor() editor.assignActiveEditor newFilename = editor.fileName logAddLine("Diff choose NEW filename:" & newFilename) End Sub Sub setOldFile If (editorsCount = 0) Then Exit Sub End If Set editor = newEditor() editor.assignActiveEditor oldFilename = editor.fileName logAddLine("Diff choose OLD filename:" & oldFilename) End Sub Sub doCompare If (editorsCount = 0) Then Exit Sub End If 'execute DiffMerge (64-bit) Set SH = Wscript.CreateObject("WScript.Shell") pspadDirectory = FileSystem.getPSPadDir() logAddLine("") logAddLine("Comparing ") logAddLine("(NEW) " & newFilename) logAddLine("(OLD) " & oldFilename) SH.Run """" & "C:\Program Files\DiffMerge\sgdm.exe" & """ """ & newFilename & """ """ & oldFilename &"""",1,1 'always select the 2nd file after comparison... Set editor = newEditor() editor.assignEditorByName(oldFilename) editor.activate End Sub Sub EditMe Set editor = newEditor() editor.openFile(moduleFileName(module_name)) End Sub ' ------------------------------------------------------------------------------ ' Default module subroutines. ' ------------------------------------------------------------------------------ ' "Init" is required ' It is called automatically during initialization to create menu items. Sub Init menuName = "&" & module_name addMenuItem "Diff choose NEW",menuName, "setNewFile", "Alt+F1" addMenuItem "Diff choose OLD",menuName, "setOldFile", "Alt+F2" addMenuItem "Diff NEW<->OLD",menuName, "doCompare", "Ctrl+Alt+c" addMenuItem "-", menuName, "", "" 'Menu divider addMenuItem "Edit " & module_name & "!", menuName, "EditMe" End Sub Then restart PSP : in the scripts menu there should be a new entry called "DiffMerge"... Now to compare any two files : (viz http://users.telenet.be/compie/20150416-PSPad-DiffMerge.jpg ) So don't matter how many files are open, I always compare new file(on the left) to the old file (on the right) : because changes are done in DiffMerge from left to right. Hope this is helpful? -- <http://forum.pspad.com/read.php?2,64632,64911> PSPad freeware editor http://www.pspad.com