Hi akelaimari, I’ve swapped the default behavior of the ‘merge Product details’ feature of our importer a few times based on different store owner needs, ultimately the ideal solution will be another import option to control how the merge feature works (e.g. import new Products and merge Products changes or, only merge Product details and skip new Products). I’ve added this to my todo list to introduce in a future Plugin update.
Regarding the exporter not exporting Products, can you please confirm what e-Commerce Plugin you are using and the version. I’ll reproduce this and see if I can issue a minor Plugin update to resolve this.