Many thanks for fixing it!
So that particular curve was copy-pasted in, so I didn't download the icon and then import it. But after that, I didn't copy-paste the icon again to other pages in the document. I can't remember if I copy-pasted the layer on the Master D slide, there might have been the original layer from which I had duplicated the pinned curve but deleted the original layer after I had finished editing the pinned curve. What I did do was pin it to the accompanying text, I clicked around pin inline with text first and float pin. (affinity publisher is still relatively new to me). I opened the pinning tab from studio, and I remember experimenting with most of the settings there for that icon. And I also experimented with resizing it and adjusting it's position, shifting its shape, and added colour adjustments to it, from the designer and photo personas. So in those personas I experimented with a bit of the styles tab (gel, neon etc), played around with the fill/gradient tool and flood fill tool, before realising i could just add a colour adjustment layer to it. But I hit 'undo' quite a lot and before I added the adjustment layers the changes I had made experimenting with the colours I had hit undo to before those changes were made if that makes sense.
I can't remember if I duplicated pages 12 & 13 in the pages list and then made adjustments or if I just inserted the Master D onto a new spread and made adjustments to that. I think I had just inserted Master D and made any small adjustments because I'm pretty sure I had already set the colour adjustment layers to that icon in Master D beforehand.
This entire document did come from a previous version of the publisher file that I still have, as in: edited that previous document and saved as a new separate document and made changes to this new one which has now become corrupted. However Master D was never in the old document, it was added as part of this new document.
- YES and no, you may not see it..