For a simple one like minimo all you have to change is the PWM levels. '0' is off, '255' is 100%.
So take the line in the original that says:
uint8_t modes[]={0, 8,90,255}; //PWM values, 5..255 - LEAVE THE "0" THERE
and change it to:
uint8_t modes[]={0,3,9,28,85,255}; //PWM values, 5..255 - LEAVE THE "0" THERE
(or, if you'd like to try it with the levels descending instead of ascending, do:
uint8_t modes[]={0,255,85,28,9,3}; //PWM values, 5..255 - LEAVE THE "0" THERE
and each short press will decrease one level instead of increase.)
(PWM values under 5 only work with the FETs, 7135s will sometimes work at 4 but not always reliably; stick to 5 as the lower bound for a 7135 driver)
luxdrv 0.30b works just the same, though the code is much more complex. You can edit the number of levels and their PWM values just the same. It gets more complicated if you want to do stuff like delete the ramping or strobe modes, you just have to comment out (add a '//' at the beginning of the line) the obvious stuff, then see if it builds without errors. It will tell you if anything is left behind that was tied to the part you commented out.
The software you'll need, at least to see the same things I see on my screen (that helps when following a step-by-step), is:
WinAVR: http://sourceforge.net/projects/winavr/ (install guide)
libusb-win32 for the driver for the USBASP programmer: http://sourceforge.net/projects/libusb-win32/
and AVR Studio 5.1.208. (try this: https://docs.google.com/file/d/0Bz85IxvlZQErdlpFYUhpbjYtZGM/edit - if you can get it to download, it should be the non-broken version of the installer, it's the right filesize)