Yeah!!! 
So impressive! I need to read the details, but I assume a lot of work went into handling the heat? As I’d like to build something super bright and hot someday, I’m going to have to learn more about thermal capacitance and conductivity.
Many thanks for your encouraging words. I’m working on it and I’m quite sure I will finish in time.
I will call my flashlight the GT4X7S.
Where have the aux leds gone? Well, after trying different connection points on the driver the aux leds finally worked when I connected them parallel to the switch leds. Only green ones worked, though. I don’t know if I used too high resistor values for the other leds, if the green ones are sucking away all the current or if the voltage sag in the long 30AWG wire is too big. It is difficult to work with aux leds as the different colors all have other forward voltages. The green leds even have 4.7kOhm resistors while the others have only 200-500 Ohm.
The four aux leds already look quite nice.
Some whitewall beamshots
You can see that the four leds form a nice uniform and round beam. The color is pretty neutral and around 4000K. The tint shift in the beam is moderate as I removed some of the yellow phosphor on the edge of the leds. If you are too close to a wall as in the second picture the beam is out of focus and you see some donut holes from the XHP70. But it is a thrower flashlight and at 50cm distance the beam becomes nicer. It has the four outer lobes which are typical for quad reflectors.
Here is a comparison between the MF04S and my modified flashlight.
On the left you see the GT4X7S, on the right the MF04S. In the second picture the hotspot in the middle is the Astrolux MF02 XHP35 which has a nice rosy led. It can be seen that the other two are not quite as rosy.
Last but not least, the night beamshots.
The settings are 2.5s, f7.1, ISO400. The tower is 700m away.
Control
Astrolux MF04S
GT4X7S high
GT4X7S Turbo
The GT4X7S has a bigger hotspot and more spill. It easily reaches a distance of 700m. It may reach even further but I have no more reference points at less than 1.5km. The beam is a bit diffuse but it has a good range and lights things up well.
The tree in the background is 200m away.
Control, MF04S, GT4X7S high, GT4X7S Turbo
Some final comments on my modified flashlight:
I’m very satisfied with how it turned out. 
The quad reflector produces a uniform beam and due to its size the throw is outstanding. I’m glad I took the work and the risk to dedome the XHP70 as it seems to really increase the range. My biggest fear was to make the leds blue while dedoming or that they turn brown. In the next days I will continue to try it out. So far, it never got more than warm also because I didn’t use the Turbo more than 20s. The color temperature is quite nice even if with 90 CRI it would be better. It is not rosy but also not green. That is why I decided to use XHP70 instead of SBT90 leds.
It turned out quite heavy with 1.73kg for only the head and 1.91kg with the battery tube and carrier. I reached my goal of staying below 2kg with the empty flashlight even though it will surpass that with batteries and it may even reach 2.5kg with the long battery tube fully loaded. As I used mostly aluminium for the spacer this year in comparison to the builds last year the weight is reasonable. It should be around 400g. The reflector is quite heavy too, close to 500g, which is 200g more than the single MF04S reflector.
All I need now is a big and empty area where I can unleash the full power of this flashlight. 
I guess with this lumens and throw it has already reached the limits of the acceptable for rural areas. 
Thanks a lot to the organisators of this years contest, everydaysurvivalgear and MtnDon, and to all the judges, participants and readers who made this another lovely contest. 
It has been a great joy for me to participate also this year. Now I have another awesome light in my collection which I surely wouldn’t have finished any time soon without the motivation from the contest.
Absolutely Beautiful Skylight
You have great vision designing this light, very impressive !
I love those auxiliary lights, good idea and the finish is perfect 
Good job posting pics and explaining along the way.
Good Luck in the contest 
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