Hi guys, all the best for the new one
I have difficulties with zphere on imac intel core 2duo :
first i draw one zphere and as soon as i want to align with shift it doesn’t work,
the sphere doesn’t align or i get this double sphere :
it seems that i am not the only one to have these problems, is there any solution ? and last pressing A for preview crashes Zbrush
for info memory setting on pref is 2048
thanks for your help 
Holding Shift while in Draw mode will create a new ZSphere of the same size as its parent. If you simply Shift+click on an existing ZSphere you are creating one ZSphere inside another - the ‘corrupted’ zsphere that you show. Trying to preview this will - unsurprisingly - crash ZBrush.
To create a new Sphere the same size as its parent:
Start to draw the new ZSphere then hold Shift. Release the mouse before letting go Shift.
Use Move mode to reposition and align ZSpheres. To create a line of ZSpheres create the start and end ZSphere then click in Draw mode on the connector spheres to create new ZSpheres.
thanks Marcus sorry my mistakes