I went out and seen that the last build was done in August of 2007 which is over a year old…
Well, if it ain’t broke… 😆
I have Firefly 1696 accessing 250GB+ / 11000 files of music running under Debian Linux – very stable (runs for months and months between mains power outages) – and I am certainly not alone in that.
As Stretch pointed out, if a NAS provider is adding Firefly /mt-daapd to their product, then it is for them to support that particular configuration and or customisation. Meanwhile, for general questions, ask away, and the users here will do their best to help you.