ASTRUM Theme: LayerSlider doesn't work / is empty

Hi everybody,
I’m struggling with Drupal theme ASTRUM and the LayerSlider. Here on my machine, I have a XAMPP+Drupal installation together with the ASTRUM theme.
ATM the theme is working, but the slider is driving me nuts.
When I go to the configuration of the slider, I have all options, but on the webpage, the slider is blank exept the navigatin at the left and right border. Same in the preview, but here, also even the navigation buttons (forward/back) are missing.
The preview generates an error in the Drupal report pointing to folder: "/layerslider/skins/preview/skin.css"
But the layerslider directory is named: ‘modules/layer_slider’

When I open the skin editor, I get this error:
Warning: file_get_contents(C:\xampp\htdocs\drupal\sites\all\modules\tabvn\layer_slider\skins.DS_Store\skin.css): failed to open stream: No such file or directory in include() (line 58 of C:\xampp\htdocs\drupal\sites\all\modules\tabvn\layer_slider\layer_slider_editor.tpl.php).
But there is no such directory ‘.DS_Store’.

I’ve checked the scripts, but without sucess. The Themeforest demo of the theme in the internet is working on my local browsers.

Please, can anybody give a hint how to fix this and to bring the slider to work ?

Thx in advance

Product Support: http://themeforest.net/item/astrum-responsive-drupal-theme/6501781/support

If you ask your question there you will be assisted further as unfortunately this is only a general Envato Community Forum and no support is offered here being product-related, sorry!