problems setting a field where to paste a video Url from youtube or vimeo

I've tried to follow the readme while setting a field where to embed a video from youtube or vimeo but it won't work for me.
What i got is the player showing with the right preset set but without any content, it is totally empty, indeed.

It is possible to configure MediaFront so that a video is pulled from
externally hosted servers or from your own files. The player can also pull in
streamed video content: YouTube, Vimeo, etc.

 1. Create a new content type. Go to Structure > Administration > Content
    types.
 2. Click Add content type.
 3. Choose a name for your new content type. You can name it "Media link" or
    anything else.
  - Optional: select any additional settings you want for this content type.
 4. After choosing a name, hit Save and add fields.
 5. In the Manage Fields section, add the following fields:

    label: Media URL
    name: media_url
    field: text
    widget: Text field

    Hit Save.

 6. In the Media link Manage Fields section, edit the Media URL settings.

    Set the MediaFront Settings field type to Media. Leave Media Type as Media
    Content.

 7. Change the Manage Display settings for Media link.

    Set up the fields in this order and with these settings:

    Field, Label, Format
    Body, Hidden, Default
    Media URL, Hidden, MediaFront Player

    In the Media URL player settings, set the MediaFront preset to nodeplayer.
    Hit Update. Hit save.

Point 6 suggests to:
Set the MediaFront Settings field type to Media. Leave Media Type as Media Content

in the manage field section of a content type where a normal text field has been created.
I cannot understand what this is about, since i don't know what the "MediaFront Settings field" is, considering that it is a text field.
The same for "Leave Media Type as Media Content", i don't know what it is about, a text field has only "Maximum length" in the settings, indeed.
So, i've simply tried to select "media front" as the "field format" and then i chose the preset i've created for.
I used to copy in a node, in the right text field, the url: http://www.YouTube.com/watch?v=k7tbGXjMRWQ that was supposed to work basing on the readme, together with other urls from vimeo or youtube.
I've the player showing, the loader on top of it but the content is empty, totally empty.
maybe i'm missing something really trivial, i don't know but i'm scared about the time i've spent to set up a simple field to embed a video on D7, i used "media" module with its helper for various provider, before and then i had to switch to media-front because it seemed very confusing..
Now i'm even more confused, anyway...
Thanks,
Da.