Just tested your Website by creating a listing and I’m able to see the issue there. Looks like the upload button is not functioning. This is normally due to a conflict with another 3rd party plugin. Could you deactivate all non-gd plugins one by one and see if it fixes the issue? Let us know how it goes.
To open a new support ticket, first select the relevant forum and then click the "New Post" button. Example: You need support for the core plugin? Click on Core Plugin support and click on the "New Post" Button.