Walter Blaser wrote:
Studio does have an option to distinguish colours in an Excel sheet.
Go to "File - Options - File Types - Excel 2007-2013". Under "Colours", you can define the colours of the cells that Studio should skip.
Keep in mind that you need to reopen your file after you have changed this setting as it is applied during conversion from source to SDLXLIFF.
Many thanks Walter, great aswer!