@jauburn
It looks I will have to update a few things on my addon (some XenForo code has been modified), but the XenForo html<=>Bb Code conversion for the list is no more accurate.
Both of the below lists will produce the same result (we're in Bb Code here):
Code:
List 1
[LIST]
[*]a
[*]b
[/LIST]
a
b
List 2
Code:
[LIST]
[*]a
[*]b
[/LIST]
a
b
To have a blank line in a list, the cariage return must be doubled
List 3: