If you had / you're having problems uploading to garmin connect yesterday / today / maybe the next days, it's their server, not my app.
See comments on their page: https://www.facebook.com/pages/Garmin-Connect/55667706445?sk=posts_to_page
I've also tried a manual upload from my PC, and it fails. They'll have to fix it, then we'll see if they made any breaking change, in which case I'll see what needs to be done to fix my apps accordingly.
If you want updates on this, please follow the sportablet account on facebook or twitter. If you won't, next time you have a problem please check the blog first :-)