Look at the old posts (in Poser tech forum) concerning readscript for V3.  The best way to put out pz2's is without :1, as this allows multiple characters to be staged without crossover effects.  But the :1 has to be removed from everything.  True without :1 then you do need to select the character first (how else is Poser to know which character? - well should be obvious if only 1 but we're talking Poser here ;-)) but as pointed out this is unlikely to be the problem here.  I suspect the problem is that Daz is still putting :1 into their characters, morphs, etc., so you need it in the pz2 file.  If all the numbers are missing, then Poser will use the default number assigned when the character is loaded, 1st = 1, 2nd = 2, etc., and the pz2 file can be blank and it will apply to last character selected - the way Poser worked back when readscript was invented - Poser 3 or 4 probably.