Hi at the lake. Cut-and-pasting the link or opening in another tab will probably not renew your ad. Just click the link in the email you received. Having the renewal emails stop for a couple weeks is the only way you'll know what you accomplished -- the ad will not look any different after renewal (yes, we wish the classifieds software was more helpful than that...).
Another workaround: Go to your ad while logged in at classifieds. Hover your cursor over the 'Product Options' link in the upper right corner of the ad. Select 'SOLD IT!' and then immediately go back to your ad; hover the cursor over 'Product Options' again and then select 'Relist It.'
Yes, enhanced classifieds is tops on my midsummer wish list.