Ok, I dont have the setup where I used a label printer to hand however you issue seems very familier to my early testing experience.
Have you got the orientation how you want it? That was my first step.
If I remember correctly my main issue was that being a cheaper desktop type label printer rather than a more commercial Zebra printer it didnt support the preferred code/lanquage for label printers.
I think I ended up using HTML coding rather than the defult <J00>/<L00>/<C00> type formatting in order to get the layout I wanted.
Firstly make sure the default setup in the printer driver is set to use the correct size label., It should be under printer preferences. Word any other software gives you ‘page size’ type options in the printer dialogue but Samba will just use the defult settings from the preferences for the printer.
If you have the preferences set right and the orientation right try reducing the line character count as this ‘defines’ the width of the paper (this is more applicable when using fixed width font) but a good place to start…
Here are some posts which might be useful when you get it running;