Can not download plugin

Dear sir!
I Can not download joomla plugin OT Before & After Image Slide from here: Notice: Undefined variable: target in /home/omegatheme/public_html/components/com_kunena/template/aurelia/layouts/bbcode/url/default.php on line 32
> www.omegatheme.com/extensions/410-ot-before-after-image-slide
When I try to download it' I get amessage: Please check your membership subscription(s) to make sure you can download the file and please check you are requesting the correct file!
Or contact us to get help!
Anybody can to help, please?
Thank you!