Ok, I attach some screenshots to explain the problems. They exist in backend and frontend.
I would like to remark that this installation is the original one from quickstart, with no changes.
First of all, backend problems.
There is corrupt demo data (no name, no images, no data, no description, no location):
subefotos.com/ver/?d7ab58a5e733b2928c86a4ebe3565a29o.jpg
subefotos.com/ver/?646bfdeb09c63aec6c7bc5fa53af2566o.jpg
Next is the problem I told you about text editor in add entry and edit view. In this screenshot you can see no space for typing, and is no posible to resize.
subefotos.com/ver/?e1388fbbe0832b764d21a5407321758fo.jpg
Now, gallery and video field, add entry and edit view too. As you can see, there is no editor visible, not even a simple text box. Is no posible to type anything and toggle editor button doesn't work.
subefotos.com/ver/?21275bdab6b016b5bbbfceae40b7df7ao.jpg
And in the next screenshot you can see my default editor, It is TinyMCE.
subefotos.com/ver/?87c651938fbe7f35b23548a364f093aco.jpg
Now I'll show you some screenshots from frontend. Here you can see how corrupt entries look like, the same as those I mentioned at the beginning (no name, no images, no data, no description, no location):
subefotos.com/ver/?d2d9ea1ffd140589d34ab1405e27cb37o.jpg
Same problem with edit view or new entry in frontend, Text box from text editor is not working in Full Description, and it is not even visible in Gallery and Video.
subefotos.com/ver/?3ddf3db9034618c69472dba1dba9d182o.jpg
subefotos.com/ver/?bebe7c452d47ab0eb03f1d3c296437cao.jpg
So, There are many things from the initial quickstart installation which are not working. And this initial quickstart is supposed to work as shown in the demo you provide at the very beginning.
At this point, after two weeks without being able to work and with no guarantee that this will be solved, I can't waste more time. Now it is not only a timing problem: I am losing money too.
I have requested the refund to Envato Market. Refund request will arrive to your mail in a few hours maybe.
I am not satisfied with how things have finally gone, and I am obviously disappointed because I really liked demo template. But right now I don't think eListing will fit my client, because he does not have enough knowledge to deal with problems like that if they appear.
Anyway I appreciate the support provided, but I will uninstall the template and look for a simpler solution for my client.