It can be a pain, but they are a pretty small company and have excellent customer service. The reason they sell B2C so successfully is because they actually take an individual brief for each "project" (read: customer). E.g What is your wall height? What are your walls made of? What are you using the shelves for? etc.
This way, not only do you get a drawing of what you are ordering (reassuring knowing the costs involved of the product) but also there is literally no margin for error. Thereby avoiding their team being overrun with calls from Maximus in Stoke Newington asking for deeper shelves for his original collection of LP's.
If I was setting up a business selling direct to consumers I would follow their business model.
tl:dr Buying Vitsoe is a process that should be enjoyed.