The Boost 'slots' (ie Green, Red & Yellow) in the Katana amps share a single set of parameters !
So if you had three different Boost devices - say, Blues Driver in Green, Clean Boost in Red, and Guv DS in Yellow - if you adjust the settings for the Blues Driver to get the sound you desire, when you switch to one of the other devices you will probably find the settings are not appropriate. Adjusting the settings for the new device will mean that when you switch back to Blues Driver, the settings you first set up will have changed - because all of these devices share the same settings.
It is almost impossible to get a usable, common set of device settings that could be shared between, say, Natural Boost and Rat !!
This same approach is true for the Delay and Reverb devices also.
Note: This does not apply to the Mod and Fx devices (which, as an aside, are the same set of devices !) which each have their own set of unique settings.
It would seem that this significantly reduces the usefulness of the three coloured slots for Boost and Delay when just using the amp's hardware colour buttons.
Good News ! : KatanaMan Pro makes this a non-issue since it saves a unique set of all of the parameters associated with each coloured slot, so that you can switch between radically different Boost (for example) settings on each of the green, red, and yellow slots and they all sound exactly as you saved them. Of course you could also just create all three patches using say Green, Green, Green button settings, and use different patches to make the changes you require.