Colin uk

The brushes are raster brushes on a vector path, (it took me a month to get this).
Within the Affinity Suite these can just be redrawn again with different sizes,
though I feel that is not what I appreciated that Designer was doing for me, that is allowing me to use vector files across different software.
Something fully in paths eg a 'Vector Pattern' brush has been requested for a while, I hope that is is provided in Affinity allowing users to export editable vector files

One vector brush
I have now discovered that there is actually one true vector brush that is usable in Affinity Designer (I have 1.10.5)
It is the 'Solid Pen with Pressure' brush found under the 'Pens' section of the stock brushes.
I selected vector brushes on the left, I double clicked the brush options (double clicking the brush) and selected 'Velocity' instead of 'None'
and in the Vector Brush toolbar selected 'Contoller -> Velocity'
The resulting icon I drew with varying width and it could be turned into a vector shape by selecting 'Layer -> Expand Stroke'
 

That is amazing to think it is completely scalable in vector format.

Use View > Studio > Text Frame, and change the path using the controls at the top of the panel.

Hi Badeend,
Welcome to Affinity Forums
This is a very old thread indeed. In v1.7 there's a new command to do what you want (the issue illustrated in the GIF above). Go to menu Layer > Geometry > Separate curves to separate the objects without closing the lines.

If you have a path, you can control if the line is inside, outside or both sides by using the Align option

 
or you could use Layer Effects to create an outline outside

I just gave it another go and the jaggy edges are not so nice.

Still waiting for true vector brushes - all but the basic vector brushes are actually rasters along a vector path, which is pretty useless for creating vector artwork and is a much requested feature - I still use an ancient version of illustrator to plug the gaps

I think these stretched bitmap vectorbrushes are mostly intended for drawing (as in big size illustrations like posters).
They are easy on the processor and work well if you set up your canvas at the right size.
 
I like the concept, but they dont do the other stuff very well. Like stretching patterns around a circle.
As a workaround you could create your design with a brush, then trace a segment with the Pen Tool and recreate it with power duplicate.
Or do those kind of effects with other programs (Inkscape 'Pattern along path' LPE).