set tmpText to read file tmpFilePath from 2 to eof 

set contents of insertion point 1 to "<" 

set tmpFilePath to (path to desktop as Unicode text) & "TmpFile.txt" 
 
tell application "Adobe InDesign CS6" 
  activate 
  set character set of tagged text export preferences to ansi 
  set curSel to selection 
  set nSel to (count of curSel) 
  if nSel is 1 then 
    try 
      if content type of selection is text type then 
        tell parent story of selection 
          export format tagged text to tmpFilePath 
        end tell 
        set curFlag to my modText(tmpFilePath) 
        if curFlag is 1 then 
          place alias tmpFilePath on selection 
          tell parent story of selection 
            set contents of insertion point 1 to "<" 
          end tell 
        else 
          display dialog "Hat nicht geklappt." buttons "OK" default button 1 with icon 2 
        end if 
      else 
        display dialog "Einen Textrahmen auswählen." buttons "OK" default button 1 with icon 0 
        error number -128 
      end if 
    end try 
  else 
    display dialog "Einen Textrahmen auswählen." buttons "OK" default button 1 with icon 0 
    error number -128 
  end if 
end tell 
 
on modText(tmpFilePath) 
  set tmpText to read file tmpFilePath from 2 to eof 
  try 
    set fRef to open for access file tmpFilePath with write permission 
    set eof fRef to 0 
    write tmpText to fRef 
    close access fRef 
    return 1 
  on error 
    try 
      close access fRef 
    end try 
    return 0 
  end try 
end modText 

set character set of tagged text export preferences to unicode