SVG files for live.menu - specific format for remap colour?

Hi,

I'm trying to create some custom .svg files to display in a live.menu and am having some limited success.

I have created some icons which work great - they load in correctly and I can use the 'Remap SVG Colors' property so that I can use the property inspector to change the highlight colour etc.

I then have some icons - created through exactly the same process, same software, etc - that load fine in to the menu, but just remain as whatever colour they were created as; even with Remap Colors ticked they don't respond to changes in highlight colour etc.

I am using Affinity Designer to create them but cannot for the life of me work out the difference between the ones that work and the ones that don't. I assumed it was down to the colour they were created in - the ones that work are black (0,0,0) so I made them all black but still no success. I have tried flattening and all sorts with no luck.

I can't find any info anywhere as to whether there is a specific format required for SVGs that you wish to be able to be re-colored. Anyone got any thoughts?

Cheers,