I uninstall many Fonts which I had extra and than I uninstall Affinity Publisher and install the old version . But didn't work with Aff. Desined and Photo because of the difference I guess ( I already had new version for Aff.D. and Ph. ) . So, than I download new version for Publisher and than all stat to work again as before. So, I really didn't know where is exactly the problem .I use Windows desktop with 12 GB RAM. ON my iPad I had a problem once with Affinity Photo because I used very big photos for photo collage . But I guess it was because of the memory of the iPad. This is my experience until now. But, in general I love this programs very much and I start to create a lot and do projects. I hope you will find the way to fix it.