Vanessa,
My viv has 2 t5 bulbs (the bluer temperature highoutput kind) and the E. nakaharai is near the top of the tank within about 6 inches of the lights. the whole vivarium is positioned at a right angle to the windows and gets a range of indirect sunlight throughout the day due to its proximity to the east-north-east facing windows. it gets oblique morning light and part of the tank gets a tiny bit of direct sun briefly around 10:30 am. my fluorescents come on around 12:30 when the sun is no longer shining in the window. The lights go off around 7pm. this time of year it continues to get faint evening light thru the windows beyond 7 pm. So for about 6 1/2 hours it is growlights supplemented by ambient sunlight.
I am always tinkering and adjusting the amount of fluorescent time and quality of window light throughout the year as the seasons change. the upper part of my windows have pieces of 60% shade cloth so the sunlight isnt too intense. it is a work in progress....
anyway, i know what you mean about Epigeneium nakaharai, it does have a fat glossy lip like Epidendrum porpax and a creeping habit as well, but they are hardly related. Epigeneium nakaharai is from taiwan and allied with dendrobium. Epi. porpax is from south america. i guess its just parallel evolution at work.
I got mine from J&L orchids. i dont believe they have any available right now...
best,
Jason