I have started a new topic.
All the limit switches work, however the middle light showing limit-switch status, does not light up.
If I swap the limit-switch inputs on the board I can confirm that the switches work, so it seems like a board malfunction?
Sending this to C3D support.
I received my new XXL just a couple of weeks ago, and after an iOS Facetime support call with Jorge (who was excellent), it was determined that I had a DOA controller board. A new one was shipped (thanks Crystal!), and in my hands in less than a week (to Ontario, Canada).
My issue was a little different to yours in that my x-axis controller was completely non-responsive right from the get-go. Quietly, I was more than a little relieved that the problem was determined to be an ‘equipment malfunction’ challenge and not an ‘idiot building it’ issue! 
Ha! Me too! I like to think of myself as a handy guy but this was something else.
C3D are sending me a new board so hopefully that will resolve my issues.
Les