Use of 2 Komplete Kontrol keyboards in live setup

Using two keyboards on the same computer isn't supported as mentioned in the knowledge base article here:

https://support.native-instruments.com/hc/en-us/articles/13143471670045-Can-I-Use-More-than-One-Kontrol-S-Series-MK3-Keyboard-Simultaneously

I'd suggest two laptops if possible, that way the keyboards will work, you have redundancy in case of a software crash and mainly because two laptops always look better than one laptop!!

what about all my other questions ?

If you want specific answers then ask specific questions including what exact model of keyboard version that you are asking about, e.g. A-Series or S-Series and which generation , MK 1 , MK 2 , MK 3 ?

1/ Is it possible to run 2 Komplete Kontrol keyboards with one laptop (Windows please) ?

No

2/ Which software would I need additionally to the Komplete Kontrol software ? Or is it possible to do everything in that program ?

There is a misunderstanding here Komplete Kontrol software is sort about 'control' and communication and when you open Komplete Kontrol then the sounds that you open are from other software (that is NKS compatible) , e.g. Kontakt. (Using the S-Series MK3 keyboard then you can also communicate directly with Kontakt 8 without using the Komplete Kontrol app) . Your question ought to be : "Which software would I need additionally to the Komplete 15 bundle software ?" And my answer would be that that would depend entirely upon what you are trying to do , right ?

3/ If it was possible to only use Komplete Kontrol software, how is it possible to set zones of different sounds for both Komplete Kontrol keyboards ? And will those zones automatically show up in different colours in the light guide ? Can I change the colours so that a lead sound always has a specific colour, a pad a different dedicated one etc. ?

I am no keyboard expert and I am not sure , also then the answer with respect to ability might depend on exact keyboard model and version.

4/ If all previous questions work fine, how can I use a foot pedal in such a setup to step forward in the songs ?

Don't know , someone else or support will have to answer this

5/ How can I integrate the iPad in this setup to display lead sheets ?

Don't know if it is possible , as far as I know then iPad support is rather limited if existing. You would have to ask support or someone else will have to tell you.

Again for all questions you might want to ask a specific question with respect to a specific setup.

If you're using Kontakt you can switch presets using MIDI. If you use something like BandHelper on the iPad you can use a foot pedal to switch between songs, then configure BandHelper to send MIDI program change commands when a song changes. You can then set up Kontakt to change presets when it receives the MIDI commands. MIDI program change doesn't work in Komplete Kontrol as far as I'm aware.

You could also try something like Gig Performer which lets you stack various VSTs and switch them with MIDI.

Not sure about the lighting colours though, I've never actually tried assigning them.

With respect to the the Light Guide programming then I spotted this :

How to create your own Komplete Kontrol light guide

How to use everything in the Kontrol S-Series MK3 , 5. Light guide (18:31)

With respect to the Setlist then I found this, however I don't know if it is also valid for Kontrol MK3 , MK3 could have changed by now , including to the better.

Q: How do you organize your setlists for the stage and the lightguide on a mk2
A: Quote : MyStudioOne :
You can cycle through your templates live with the preset up and down buttons on the MK2

With respect to using Kontrol MK3 then some other users has discouraged that. While I can say nothing about their general criticism then I must agree that there have been a number incidents where Native Access has suddenly made peoples setup go haywire one way or the other. So at least it is very much advisable to not use Native Access to update or anything shortly before a gig as well as also having a backup of it all in a state where it is all working OK so that one has that to fall back on. Ref. : Using S61 mk3/Komplete Kontrol in live/stage scenario

I am sure that Matthew_NI does most likely not agree with the above but I can try asking if @Matthew_NI do you have anything to add on the topic of Light Guide and Setlist and any eventual improvements made in the Kontrol S-Series MK3 ?