If you did not do so already, in nd_ec135 copy a Texture.x directory to Texture.x+1
(example: Texture.5 to Texture.6)

Place this in your nd_ec135 aircraft.cfg

[fltsim.6]
title=EC135 KLPD
sim=ec135
model=2
panel=2
sound=
texture=6
kb_checklists=ndec135_check
kb_reference=
atc_id=PH-PXA
atc_airline=none
ui_manufacturer="Eurocopter"
ui_type="EC135"
ui_variation="KLPD (P2i)"
ui_typerole="Rotorcraft"
ui_createdby="Nemeth Designs"
description=

Overwrite the .dds files and the thumbnail.jpg file with the enclosed ones...

Enjoy!