My portable freezer is just below 0 C; water takes quite a while to freeze in it. it's definitely not a cold as a normal freezer.
Is this cold enough for freeze precip?

I would say no, unfortunately. If you evap the NPS so that it's super-saturated, then you'll likely get some goodies, but the freezer needs to be COLD for it to drop everything out. I've seen reports of a good deep freeze basically precipping everything other than a small single percentile of the goodies out of it.

The freezer's gotta be cold enough to make ice cream hard. If you pull the vessel out of the freezer and there isn't instant water condensation freezing on it, it's likely not cold enough. Sorry!

it makes sense to me that....If freezer is cold enough to ..[freeze water hard].. after all night.. it shouldbe cold enough to percipitate goodies desolved in napatha...

This asumption may be off some.. but why does one need sub freezing temps to percipatate spice/?

I also find that..[ supersaturation of napatha].. makes it not nessesery to use a freezer at all..
Just use 3 or 4 hundred grams of good bark and supersaturation is easy...

[[photos below]].. of my last supersaturated pulls with crystals forming all over the jar at room temperature very fast!.....
I simply pour off the exess napatha into a clean jar. and quickly fan dry the mushy crystals to a powder....
Then take the dryed crystals and desolve then into grain alcohol ..then re evaporate and repeat the procedure atleast two times to get rid of ttrace napatha...
If something is wrong with this procedure ..please let me know..
But ive tryed my product with no ill effects...