However, since installing the Simple Analytics upgrade, eCommerce is definitely not working. I'm still getting traffic results, but no sales have registered since the upgrade.
This is exactly what I am experiencing. Might be time to bug-check the contrib.
I did notice that the header on google_analytics.php is still listed as 1.2.0 vs. 1.2.1 Probably just an admin oversite, but figured it was worth a mention.