Operating system: Windows 10 (Anniversary Update)
Dual monitor setup
One monitor is a 4K screen (3840 x 2160) set to 250% scaling
The other monitor is (1920 x 1080) set to 100% scaling
Affinity Photo Version: 220.127.116.11
Steps to reproduce:
Simply open Affinity Photo in the 100% scaled monitor.
Select a tool (other than Move Tool), and move cursor over your image, it will be very large and pixelate (see screenshot with View Tool, large hand icon)
If you move Affinity back to the high DPI display, tool cursor is perfect there.
Move Tool, which seems to just use default cursor does not have this issue.
Otherwise, I am super impressed how well Affinity works already on High DPI displays and multi monitors, it's not yet perfect, but far far better than a large number of Windows programs and competing photo editing apps. Well done!!