Topic thumbnails shown only for the joomla/moodle admin

Hi,
My course has a picture thumbnail in each topic. In Joomdle, in the Content module, they are shown only to the administrator user but not to the students.

Any ideas why this can be happening and how to fix it?

Joomla 3.4.3
Joomdle 1.0
Moodle 2.8

This is how a student sees it

This is how admin sees it

You can check broken image links, to compare them to working ones.

As I see, both working and the broken links have same URL

This is the URL of the working image
<img src=" igzaat.org/moodle//auth/joomdle/pluginfi...ction/16/epiteti.jpg " alt="" width="140" height="140" role="presentation" style="float:left; margin: 0 .5em 0 0;" class="img-responsive">

This is the URL of the broken one
<img src=" igzaat.org/moodle//auth/joomdle/pluginfi...ction/16/epiteti.jpg " alt="" width="140" height="140" role="presentation" style="float:left; margin: 0 .5em 0 0;" class="img-responsive">

I see you have a double slash in your URL. I guess that's not the problem, but it is better to remove trailing slash in Joomla and Moodle URLs in Joomdle configuration.

As for the content: is it a label or is it section summary?

Thank you Antonio,

This is strange, as I do not have a trailing slash neither in Moodle nor in Joomla, or am I looking in a wrong place? See the attached.

As for the thumbs, in the example I gave they are the section summaries. Though, the behavior is exactly the same with the labels when shown through Joomdle topics.

Yes, it is werid, as you have correctly set both URLs.

As for labels: I know last Joomdle version fixed a problem with labels in images, so you should upgrade.
I don't know if that will fix the issue wirh the section summaries, as I cannot test myself right now.