SRA clerk here. Seriously guys, you should register. It's for your own good. And before you guys go all 'Oh human specist bastard', I'm also 1/8 satyr and 1/6 river drake with minor natural psi.
Look, if you don't register, you're counted as a normal human, or nearest equivalent species for legalities, but your powers are still considered pretenatural abilities. So step out of line in the least, even by accident, and use of an unlicensed pretenatural device is slapped on to the charges, which, as you know, basically guarantees 4-5 fold increase in sentencing severity. On top of that, most countries require registration in order to be considered a citizen. So if you're an unregistered legal, you're now an illegal. Which strips away most of the protections the law affords. And if you're an illegal, well, a lot of countries still have witch hunting laws on the books - a lot of humans hate us, guys. So they can have a nice necktie party or whatever without any legal repercussions.
And that doesn't even include an inability to own land (unregistered dryad? Good luck hanging on to your tree) or other forms of property. Not to mention being able to petition for species-based exceptions in the work place (not being able to work by day or during a full moon, etc).
The SRA does all that for you, in addition to supplying you with legal counsel and various other supports. Even if the worst of the rumors were true, you'd still be better off registered.