Not sure Peter, but that might be one to ask Wahoo. Try opening the file you downloaded from plotaroute in a text editor. You should see the name of the route in the file. Does it look correct in the file? If so, it must be connected with the import to Wahoo somehow. If the name looks wrong in the file, let us know what route you're downloadeding and what download settings you chose and we'll try it here.
When I create and download a route to my Wahoo Roam its shown as a mix of numbers and letters even though I give the route a name. I looks correct on my phone but not on the Wahoo. This has only been happening for around 14 days, before then it was showing the name given.
Any ideas?
Thanks