Since I can't manage to print in VB6 with high quality (with every code I try, the printing looks pixelated and grey)... I resolved to export:

* via RichTextBox, to Microsoft Word
(.SaveFile FileName, and then opening it in Word via Shell)
* via SpreadSheet, to Microsoft Excel
(.Export FileName, and then opening it in Excel via Shell)

...the thing is I don't know:
a) how to set the margins
b) how to tell Word and Excel to print automatically, without the user having to click "print"

Does anyone knows how?
Thanks.