Another category with the same parent category has the same alias

Hello, another 3 days have now passed. I am unable to import even Categories, let alone Articles and third-party extensions. I was under the impression that this extension would accomplish the importing quicker and easier than manually doing so, and that the customer service would be more responsive, but it has now been days with no progress rather than completing the entire job in a matter of hours. I am very dismayed.

Does anyone in this forum know of any other third-party extensions which perform the same promised function as this one? I need to move forward with this project. Thanks in advance.

Submitted as requested, Daniel. Thanks in advance for your looking into this. I really want your extension to work for me.

I want to be sprinting with this extension, but I am crawling.

I'm trying to import Joomla Categories from one Joomla site (the donor) into another (the recipient). I'm doing the Categories first, BEFORE then proceeding to similarly import all of the Articles

From the vData control panel, I am clicking "Import". Then, I'm entering all of the remote database details for the donor site. I click the "Continue" button at the top left. On the next screen, I select all of the drop-down values on that screen, and then click the "Import" button at the top left.

And then I receive the following error message:

Another category with the same parent category has the same alias (remember it may be a trashed item).
Import Failed

Needless to say, I have changed the alias names of all of the Categories (there are only a handful) in the recipient site, to remove any potential conflicts with the Categories that I'm importing from the donor site. And yes, I have checked the Trash to make sure there's nothing in there with an alias that might conflict.

Is this forum the only way of getting support from the developer, or is there a more direct way to request support? This process of bringing in the data from one site into another is ending up taking me days rather than minutes/hours - and I haven't even gotten to the Articles, let alone the third-party extension data!

Thanks in advance.