Please give me your license key in a private reply and temporary wp-admin login info in a private reply to check, it could be caused by your server firewall.
actually it is not related with download manager, it is related with a php function imagejpeg, probably, those are other type of image ( ex: png ) where extension is changed. You may try with any other random image, they will work fine.
New usage: http://www.wpdownloadmanager.com/download/wpdm-accordion/
Now you use use additional parameter cat_style to change top level accordion style, as value you can use info or primary or success or inverse or warning or danger or default
And to change inner level accordion style use parameter subcat_style
When you are not logged-in, you will see login form in the page where you used short-code [wpdm_user_dashboard], if that is not the issue, may you please explain little more with example.
The error was showing because you use port number with ip, however I removed port and now it looks like it required sftp, but for now the add-on only can connect with ftp. However we shall add ssl support with the next update of the add-on.
I see there is a file name mismatch issue in your installation. Probably some files were not updated properly when your were updating plugin. Anyhow I’ve adjusted it and everything is working fine now.
