Same as mine.
You need something that fits in the groove. You also may have to snap off the metal punched part that is inside the hole.
Homebase is rubbish quality shocker!
Slightly more seriously, this thread is exactly the sort of reason I stopped buying stuff from homebase, the quality of a lot of their goods is appalling - screws that break or bend (often less than halfway into the supplied rawplugs), kits (like these shelves) that require you to know you have to add something to rectify a basic design fault (you shouldn't need to pack it to get the screw to fit properly).
I appreciate that you're trying to help, but I just don't understand you.
I understand the dowel concept, and I understand that the screw grips the dowel and that holds everything straight.
However I don't understand how I can get a dowel up there without it being loose. I don't understand what you mean by a groove, and there's a metal punched part up there?
Pinter and that's my complaint with kits that don't have everything needed and don't say you need to do something like that
the_halk, if the rawplug is spinning in place you can either use something like nonails to help fill the excess (leave it to dry for a while), or there is a specific filler for loose plugs, but I can't think of what it's called.
Ok does this help explain what is happening, and how you fix it?
It is a very simple hack!
The bit where it says Screw is pulled upwards should be Shelf is....
I was lazy and copied and pasted!