Hi,

I have finally figured out a way to have a top-down layout in Trados so I wanted to share it:

1. Export the untranslated sdlxliff to Excel using SDL XLIFF Converter for Microsoft Office which is under the Welcome section

You will get an excel file with all the source segments and the segment numbers

2. Make excel an "always on top" window using autohotkey. See here: 

https://www.howtogeek.com/196958/the-3-best-ways-to-make-a-window-always-on-top-on-windows/

3. Get rid of the things at the bottom of the window in Excel under the options (sheet tabs and horizontal scroll bar) and even the status bar with a macro. See

https://www.extendoffice.com/documents/excel/673-excel-display-hide-status-bar.html

You can now place the excel file with the target segments on top of Trados to have a top-down layout. This also has the added benefit of allowing you to edit/format the source as you like. Transtools is also recommended if you want to merge split segments easily.

Hope this might help some Trados users!