Thanks @PhilipDAth That isn't ideal but would be acceptable. I gave it a go but as I need to recognise traffic on a particular port I created the below:
Now on the clients screen when I look at the custom pie chart I get:
More than 90% of the traffic for the network is on port 7563 and it was added last week, but it looks like the custom slices don't work with custom ports!
If my answer solves your problem please click Accept as Solution so others can benefit from it.