If you want to change the source code, edit the .jal files with a text editor (i used jaledit: http://www.esquire.co.ae/sunish/html/jaledit.htm)
and compile it. I used jal-0.4.60.win32 (http://prdownloads.sourceforge.net/jal/jal-0.4.60.i686.win32.zip?download)



If you just want to program the pic, all you need to do is upload the .hex file into the pic:

Make a pic programmer like this one:
http://www.circuitsonline.net/circuits/view.php?id=91
or
http://www.jdm.homepage.dk/newpic.htm (i think this is the same, not sure)

connect it to your serial port of your pc, download ic-prog (http://www.ic-prog.net)
start it and choose PIC 16F628, set the correct com port, choose oscillator INTRC I/O, uncheck MCLR.
Load the hex file and press program all. That's it. Good luck!
