Serpentine/auxiliary/drive/alternator belt routing

[madted21]

Hey all. Sorry if this appears elsewhere, I guarantee you I've spent hours and hours searching for the answer to this question.

I have a 1.6 e-hdi (don't ever get one) multispace on a 13 plate and the serpentine/drive/auxiliary belt snapped. I cannot find anywhere online or in books that looks quite like my engine. Close, but not the same.

My issue is that the same belt (same make, numbers and length) that snapped won't go back on! It's not even close, even with the tensioner right forward.  I have attached a pic, basically mine looks like the picture, but with an extra pulley that I've drawn in red. Then drawn where I assume the belt should go, but it's way too short. 

Any ideas? Please help ha ha