Resolved Export/Import VM Products

The Clone

You select one or more fields and click the clone button and the selected fields will be duplicated in your template.

QuickAdd buttons

You click it and you get a popup with all the available fields and you can select which ones you want to add to your template. After selecting them you click Add fields and they will be added to your template.

How to properly duplicate a template so that I can modify a copy and leave the original unchanged?

It should be as you said, the Save as new button to do that for you.

The whole template system has been overhauled in CSVI 6 Pro so that won't be an issue anymore.

Thank you, they are all exporting now. Can you point me to documentation that explains the following:
The Clone and QuickAdd buttons on the Fields tab of a template;
How to properly duplicate a template so that I can modify a copy and leave the original unchanged? (It seems when I click Save As New sometimes I end up with the same template but with every field duplicated.)

The problem as far as I can see is because not all your products have a product_sku. CSVI requires this field to be filled and to be unique. After you have updated your products with an SKU, run your export again and you should have all your products.

I solved my other problem with importing users after restoring from a backup, however the export of products is still only exporting a subset (the same subset) of products. Can you help with this?

I attach the log, the exported file, and exports of the virtuemart_products and virtuemart_products_en_gb tables so you can see that there are 20 products and only 10 are being exported.