How convert Hex file to SOF, POF or any format for use with USB Blaster

Converting a hex file to a sof or pof file isn't possible because the sof->hex conversion is lossy (though most of the things which are lost aren't that interesting - just dates and strings)

You might be able to convert it to a pof file with a couple of hours work - the format is available on the web - start with a blank pof file for the right device and replace the contents of the appropriate section with the data from the hex file