Ian,
I was unable to save a modified signature over what was already there until the slate was wiped clean by saving it blank first. I tried several times prior and it always reverted back to the previous entry. Hope that clears it up.
It appears that I'm also unable to modify my signature. I have it saved and it passes the check but still shows all wrong.
This is how I have it saved under settings:
FSS0371695 NA KSEZ Sedona Airport | FSS0308338 NA WA79 | FSS0295595 Global VECTOR | NA Blue USA/Canada Pacific Northwest | NA 05S Vernonia Municipal | NA 11S Sekiu Airport
FSS0281604 NA Blue USA/Canada Northern Rocky Mountains | NA 65S Bonners Ferry | FSS0231928 Global | FSS0114429 Australia SP4 | AU YBBN Brisbane International | AU YMML Melbourne International v2
**EDIT** Once I deleted the old signature and saved it blank then updated and saved it works.. Just an FYI for anyone experiencing the same thing.