In reply to NomadET:
Yes I've figured it out. It's multiple bugs in the app.
For whatever reason, random network issues perhaps, the app failed to authorise your account with the server. (bug 1 - it should retry this)
It turns out that if you're not signed in to the app you don't get to access the ukc crag data (bug 2).
Finally, (bug 3), it fails to give you a reason for not fetching any data.
The reason I couldn't recreate the issue was because I was signed in fine.
You will most likely be able to 'fix' the issue by killing and relaunching the app, or by signing out and signing back in.
Post edited at 12:22