If you NSIS 2.0b or the latest CVS, you can put the fonts.dll-file in the 'Plugins'-directory of your NSIS installation. In the script, extract the font in a temproary directory using File and GetTempFileName. Then you can use the following code instead of your own code (change CFBSFONT.TTF to a suitable path):
But read this
thread carefully. You also have to change or add some registry values and stuff.
If there are still any questions, post your complete script as an attachment and someone will help you if possible.