Help: I have taken my Henry red turbo brush thing apart and can't put it back together

[Lalsy]

That's it. The roller was covered in fluff and thread and I couldn't remove them so I unscrewed the four little screws and opened it up and cleaned the roller and now can't fit it back together. There is this white spiky thing and I can't remember how that was positioned so the two halves close.

Gibber gibber. Can anyone help me please?