Unable to import excel column list in Union Transformation

Hi,

I am trying to import a list of columns into Union Window using import excel feature but nothing is imported in the grid

See my two attempts below

 
 

The stoic Union Window after the import, without giving any errors 
 

 

OK just figured but how to make red works since it's so prominent


 

We will have a look at it for you 

Quesiton 
is this entire grid (of mapping) case sensitive? 

Yes, it is

admin wrote:

Yes, it is

I kid you not , I spent hours yesterday figuring what was wrong with this my import. Can I suggest at least put this content(somewhere) on the grid regarding this for other newbies?