Ok, I'm trying to do this - export all my products as an XML, import that XML into Excel spreadsheet, edit and add new products/categories/etc in there, and then export it into XML that I will upload in the ubercart and maintain all the products like that (just easy to control all the inventory).

Now, the problem happens at the importing and exporting from Excel stage.

While importing the data, I get this error:

there is a problem with the specified XML or schema source. click OK to have excel create a schema based on the XML source data

so sure, I click OK, and it creates a pretty decent spreadsheet of all the categories, products, attributes, etc.

now, when I try and export that same sheet (without even editing it a bit), I get these errors:

store_map is not exportable because it contains the following:
- list of lists
- a mapped element's relationship with other elements cannot be preserved
- denormalized data

So, there goes that idea of using Excel to manage all the products.

Any suggestions here? What do you guys use instead? And how do you manage this offline, if at all?