I hope this is the right place to put this, it is the nearest I could find. If not feel free to move it.
Anyways, I know that until SimPE is updated to FreeTime there is a list of things it can safely be used for and things you can't use it for without risking hood breakage. I was wondering if anyone knows which things are which. I think having a post stating which are and aren't might save people (like me) a lot of needless mistakes.

You can't do Sim Surgery or extract Sims.
I'm pretty sure you can still make objects and object recolors, though.

I am guessing it would be unsafe to open a neighborhood to swap my nightlife template for a different one via the MATY tutorial then? I mean if extracting sims and sim surgery is a bad idea?

I've done that when Seasons was out and SimPE wasn't updated yet... Bad idea. I've screwed up the whole neighbourhood, causing me to start all over again.
If i were you, i would wait until SimPE is updated.

Anything that requires opening the neighborhood browser is unsafe, basically. You can -try- extracting sims but make a copy of your Neighborhoods folder before you do so as it's possible even trying to open it without saving anything might screw things up - definitely trying to modify or save any sim info or anything like that in the neighborhood would be a Very Bad Idea.

What -is- safe is all other sorts of creation: you can still recolour, clone, make defaults, open custom files, make careers, open game files to extract bits and pieces, etc., with no risk. Just don't do anything with your existing sims and neighborhoods till it's updated.