Hi Aleksandr,
I've used Zebra printers in the past and have quite often ran into issues printing labels with Crystal. They are a good printer and expensive and when things don't work then it's hard to deal with.
An alternative printer are the label printers from Dymo. They are a lot less expensive and I have never had an issue setting it up and working with Crystal Reports.
I haven't used it with the viewer but I haven't had any issues with the .NET applications I've written either.
Good luck,
Brian