Numinix has uploded on his site a new version 1.12.2

I can NOT replicate as far as i can see most of the error pointed out
As Duplicate categories etc

As per shipping
You need to:
1)You NEED set up your shipping options on YOUR Google Merchant (google site)
go to google.com--My account look for Merchant Center link

Settings--->>Tax and Shipping

Under Shipping Create New Method

My case I use Carrier-Calculated Based on the USA
I created for the 3 companies UPS FEDEX and USPS
one of each shipping method

For Last on Zencart

Enable Show weight On Configuration Google Merchant Center

So far so good

Keep in Mind that I DO NOT have any attributes on the lisitin in which I have not tested

Zen 1.3.9h

Good luck