Hi @Dan C Just noting here for anyone else searching that with my older Wacom Bamboo Fun CTH-661 using Wacom driver 5.3.5.3 (the latest driver for this particular tablet) on Win10Pro v1909, there was no pen pressure sensitivity in Affinity Designer 1.8.3 vector brushes until I read your tip about the Controller setting. I've spent a couple of days rooting through forum threads, but your comment was the first one that got the pen pressure to work, so thanks for that. Is there a general Designer "Troubleshooting" thread I may have overlooked where all these tips are stored?
Also, turning off Windows Ink both in the Wacom Tablet settings and in Designer didn't change pen sensitivity in Designer, but it did cause my pen to jitter/map wildly after restarting my computer. I didn't change any of the Ink settings in Windows itself. After I re-enabled Ink in the tablet and in Designer and then restarted my computer, the issue resolved itself.
As an aside, also as a newbie to Affinity Designer, I found it odd that pen sensitivity isn't available from the get-go after opening the program and actually needs changing settings.