Hi Matthias,
The answer is to create a new Live Set listing that reflects the new order, then Exchange the new ordered list with the original. Each PAGE can be named as you require

If you know how to setup the first arrangement of Performances... setting up the new order is just as easy... just do it to a new Page (there are 16 Pages in each User Live Set Bank) or in a new User Live Set Bank (there are 8 User Live Set Banks)

Here is what I recommend:

Press [LIVE SET] and recall slot 1 of your original Set list.

I assume by "Preset" you are referring to the fact that Slot 1 is a Preset Performance... start with that one.
Hold [SHIFT] + [LIVE SET] to Register this Preset Performance to Slot 1 on the next PAGE (or the next USER Bank)

You advance to the next PAGE within the current User Live Set Bank using either of the following methods:
1) the Down Page arrow in the screen (top right) shown below with a red box around it
2) the [PAGE] buttons on the right half of the front panel
3) The dedicated Down [PAGE] button on the lower right front panel

You advance to the next USER Live Set Bank using any of the following:
1) The Down Bank arrow in the screen (top left) shown above with a yellow box around it
2) The dedicated Down [BANK] button on the upper right front panel

Return to your original LIVE SET, select the second item,
Hold [SHIFT] + [LIVE SET], to register it, select the second slot on the next PAGE (or the next USER Bank)
Place the flashing white box by touching the location and then tap it to place the Performance.

Rinse and repeat... return to your original LIVE SET, select the next Performance you want and you are simply pasting it into a new PAGE or USER Bank Slot.

Once you have generated your new listings, you can EXCHANGE the entire Page or User Bank with the original.
The LIVE SET EXCHANGE is described in the Montage Supplemental Manual that came with the Firmware update.
While in Live Set, Select Bank and Page to be copied or Exchanged, press [EDIT], then hold [SHIFT] + [EDIT]
Entire Pages can be copied or exchanged

Once you know how it is quick an easy.

Follow-up Questions:
If you were thinking you could just drag and drop the registration as you do Apps on your phone, no, sorry you can't.
If the post was to inform us that 'wouldn't that be cool', well, yes it would!
If you want to know can you Insert a Performance and have the others move aside, no, sorry you cannot.
If you are going to ask if this could be added in a firmware update... duly noted.

As a test, I did what you asked in well under minute.

Hi!

Forgot to answer and say thanks for the reply!

I'm all good now. 😉