ZBrushCentral

Beginner problems...

Hi,
I am trying to get myself re-aquanted with Zbrush after too long of a time, and I keep getting stuck and don’t know how to fix it, or what i’m doing wrong in the 1st place.

One thing that keeps happening when i’m making z-sphere armature/model is that I get so far along, then sometime after I have turned SYMMETRY on to add the arms and legs I find that my symmetry has somehow ‘jumped’ and as i’m moving say the elbows, only one side will move, it’s as if i’ve somehow knocked it out of line…I think it ‘may’ be due to me being lazy, because sometimes I will
leave symmetry turned on, yet only add a single z-sphere by making the two selection circles overlap…I try to be accurate, but maybe I should be swiching
symmetry off to say add the neck, or hips etc…??
So I don’t know how i’ve caused this problem, and also I don’t know how to fix it…I’ve tried various things like switching symmetry off then back on, i’ve even pressed a few likely looking buttons but no joy…

Can someone tell me how i'm screwing up and If/how it's possible to fix

so my model regains it’s symmetry?

One other problem I found yesterday was I wanted to learn how to make a diplacement map, then apply it in Maya, either for Maya render or Mental ray…But i couldn’t find a tutorial with how to do this in 3.5, there are many showing how to do this in ZBrush 2, so many in fact that it’s hard to find anything else on say You Tube…I’m sure there is one, and I read that you can now export to Maya format, but when I tried fumbling along, I wasn’t too sure if i had the settings correct . (If I remember correct, i had lowest subdiv lvl selected, AUV swiched on, and the settings I had were 32bit,Flip V, and 3 channels) then exported mesh as .ma

I was kind of guessing at this point, so I put a Displacement shader on to a Blinn and added my File texture, then without setting anything, started a render in maya s/ware ---- It didn’t look pretty…
Maybe I should have used Mental ray, and used a subdivision approximation, but I reckoned it ‘should’ render in Maya - I couldn’t see why not…
I haven’t put any figures in, or adjusted anything, so that must need doing I think…??

Could someone please point me in direction of a tutorial showing how this is done please? - Or if i'm not too far off the mark, let me know what i'm doing wrong, or where and what I should dial in to Maya..... Thanks in advance, would love to be able to create something even half decent in this awesome program............. Scraggy D