Looks good vurt! :thumbsup:
Trees are generated as distant statics correctly by MGE and render correctly in Mournhold interiors at distance. The only problems I see are some obvious clipping along the walk way in Mournhold Great Bazaar, and very minor clipping in Godsreach with one lamp post and along some of the buildings (really not that noticeable).
The nifs themselves have some extraneous empty children referenced in some NiNodes and NiTriShapes:
flora_tree_mh_01
5 extra 'None' children refs in root NiNode
1 extra 'None' children ref in both NiBSAnimationNode 3 and 14
flora_tree_mh_02
4 extra 'None' children refs in NiNode 21
1 extra 'None' children ref in both NiBSAnimationNode 3 and 14
NifSkope can be used to collapse those nodes and clean out the empty references. Such refs can cause issues for MGE during distant static creation, however for these nifs the extraneous refs do not appear to be causing any problems.
You'll probably also want to do versions of flora_treedead_mh_01.nif and flora_treedead_mh_02.nif, so that the dead versions will match up with yours when the appropriate time comes during the tribunal quest line.
[edit] added extraneous empty children refs for flora_tree_mh_01
Also noticed that the RootCollisionNode wasn't lined up as well as it could be - made these adjustments:
flora_tree_mh_01
translation - X: 4.0000 Y: 14.0000 Z: 160.0000
scale: 0.7000
flora_tree_mh_02
translation - X: 0.5000 Y: 15.0000 Z: 369.0000
scale: 0.2200