Sussed the modes out today - paid it a little more attention.
When the light is off, hold down the switch (only half cover it because you need to see the colour the switch flashes...). Wait for it to do the 5 very fast flashes, and carry on holding the switch down. you will get 3 red flashes (slow flashes), 3 green ones and then 3 more red ones if you let it cycle through all of the modes.
Where you let go of the switch is the program you get... so if you let go after 3 red flashes and 2 green flashes, you will have mode 5 which gives you 3 hours on high and 10 hours in medium with no 'low' setting. If you let go after the first red flash, you will be in Mode 1 which gives you a run time of 2 hours in 'high' mode, 6 hours run time in medium mode and 12 hours in low mode. You enter the modes once the light is on, but pressing the switch once briefly again - so you can dim it for oncoming vehicles when cycling on unlit lanes at night etc. Hope that helps - if not PM me and I will try to explain it more clearly...
