I have about 4 of these guys, grown from seeds from the ICPS seedbank.
They are in the basement under lights with my other highlanders. They are very slow growing, and seem to just struggle along for me. I can't remember for sure, but I think they are in straight LFS, or mostly LFS with a little of the "Deluxe Mix" from The Savage Garden Book. My largest trap is about 1 inch tall. Due to lack of space, one of the plants is not in a terrarium - it has no pitchers at the moment.
Occasionally I'l the feed the plants that do have pitchers a kind of Beta fishfood called BetaBioGold. Tiny round spheres - about the only thing that will fit in the traps.
N. madagascariensis is supposed to be a lowland. I've tried it in highland and lowland conditions and it doesn't really "do" anything, so i've crossed it off my list for good. Can't keep it alive either.
Yeah, you're a master grower if you can blow us all away with your N. madagascariensis!
Mine actually grew pretty well in a tank I have at work. 60-80degrees all the time, under fluorescent tubes. But I took one business trip where the person I appointed to water the plants forgot. The plants weren't happy, but only the N. madagascariensis died. I say give it a try, though. Maybe it's just misunderstood. Maybe it just needs the right person to grow it!