Created attachment 124275 [details]
Create a document with two custom styles (that inherit from nothing). Style CustomLevel1 and CustomLevel2.
In edit paragraph style -> outline & numbering, select numbering style "numbering 1" for both those new styles.
Now, for CustomLevel1, in style -> outline & numbering, select outline Level = 1.
For CustomLevel2 , in style -> outline & numbering, select outline Level = 2.
Add a line of each style.
Even with specifying custom levels, at the end both the lines are level 1.
Of course, it remains possible to modify the level using the IncreaseIndent button of the interface, but the change is not saved in the style (it's just direct formating).
Normaly, applying the style CustomLevel2 should directly put the right level to the text.
Maybe the outline level parameter (that doesn't seem to work) is not exactly the parameter to modify.
But in that case, it seems that today it's not possible to create custom styles that are equivalent to Heading* (even if we use inheritance, that doesn't work)
*** This bug has been marked as a duplicate of bug 42920 ***