For anyone else that plays CoX on the Rebirth server on Linux, Wine has a problem using https. Since Rebirth primarily uses https addresses this means the standard URL for the Rebirth manifest file, and the Rebirth manifest file itself, will not work with Wine. However there is a workaround.
Download the manifest file and save it into your local hard drive.
Open the manifest file in a text editor like Gedit or vi.
Change all instances of https to http and save the changes
Point your preferred launcher (tequilla, creamsoda, or sweet tea) to the locally saved manifest file.
Be aware that after doing this that any changes to the manifest file by the Rebirth community will of course not update automatically. Any Linux users doing this will need to pay attention to announcements and manually update their manifest file every time an update is released.
Along those lines, if possible I (and any other Linux users wanting to play on Rebirth) would appreciate an alternate version of the manifest file that uses http instead of https hosted online. I understand the increased safety and security that https affords and absolutely recommend keeping the https version as the “primary” one, not even offering a link to the http version on the homepage. However having an alternate http version that can be posted here in the forums for other Linux users that run into this bug would make things easier for us.