Niko - if you go to the MATLAB File Exchange and download the submission findjobj and save this file somewhere in your MATLAB search path, then you can update your GUI with the following two lines of code that will set the caret to the end of the line in your edit box so that it creates the appearance of automatically scrolling to the end
% assume that the text box that has been updated with the user input is named
% text1
% after text1 has been updated, move the caret to the end of the line
jhText1 = findjobj(handles.text1);
jhText1.setCaretPosition(jhText1.getDocument.getLength);
I tried out the following by creating a simple GUI using GUIDE. (If you created your GUI in a different manner, then you will just have to replace handles.text1 with the handle to your non-editable text box.
The above worked in my version of MATLAB R2014a on OS X 10.8.5.
