You can get support for Zebra from at least three sources.
First, there's the Zebra web site at http://indexdata.dk/zebra/, which always has the most recent version available for download. If you have a problem with Zebra, the first thing to do is see whether it's fixed in the current release.
Second, there's the Zebra mailing list. Its home page at http://indexdata.dk/mailman/listinfo/zebralist includes a complete archive of all messages that have ever been posted on the list. The Zebra mailing list is used both for announcements from the authors (new releases, bug fixes, etc.) and general discussion. You are welcome to seek support there. Join by sending email to <email@example.com>. Put the word subscribe in the body of the message.
Third, it's possible to buy a commercial support contract, with well defined service levels and response times, from Index Data. See http://indexdata.dk/support2/ for details.