I'm not actually sure if this is related to New-Nav or not but I was just looking for this bountied question:
And thought... OK, I'll go over to the "bounties" tab...
But it isn't there.
Sometimes when I come back to the Meta main page, the bounties tag has incremented to "8"... but when I click on it, it drops back to "7" and only seven questions (as seen in the screenshot above) are on the list. It seems that it's trying to add it to the list and failing?