Hello Carsten,
a forum meber - IanS - sums it up pretty well why DXO does not have a history panel:
"A history panel is a normal feature for a pixel editor like Photoshop. This is needed because each adjustment builds on the previous one and the order of making adjustments is fundamental.
DXO-PL 2 is a parametric based raw converter. With a parametric editor you are just recording the instructions to be applied but they are not actually applied until you export the raw file to a RGB image. Therefore the order of adjustments does not have any meaning.
So for example in a pixel editor if you start off by adjusting contrast and then later on think I need less contrast you can step back to the contrast adjustment in history and change the contrast. Unfortunately, this will then mean that you have to do all of your other adjustments again. Not a good way to work.
In DXO-PL 2 if you started with a contrast adjustment and then later on want to reduce contrast you just do that and you still retain all of your other adjustments.
A history function is vital in a pixel editor but not required in a parametric editor. Why would you want to loose all of the adjustments after a history point when you don’t have to?
I hope this helps explain why DXO-Pl 2 does not have a history function.
Ian"
Here is the full thread: Confirmation of "undo"
So what Alex is describing is NOT a work-around.