Hi Thor 
:large_orange_diamond: Use the '+' and '-' to zoom in/out.
:large_orange_diamond: ZBrush will zoom into the area that is pointed by your cursor.
:large_orange_diamond: Press the 0 (zero) key to set the zoom to actual size (x1)
:warning: To find other shortcuts, simply point to any of ZBrush's interface buttons and if that button has a shortcut, it will be displayed at the top-right of its pop-up info window.
Other imported hotkeys are…
pressing the Alt key while drawing will reverse the ZAdd/ZSub state. (i.e. If you are painting with ZAdd mode selected, pressing the altkey will allow you to paint with ZSub mode)
If you are using a graphics tablet then you may use the ‘eraser’ side of the pen instead of pressing the alt key.
Pressing the ctrl key while drawing on an edited 3D object will allow you to apply masking to the object. (pressing ctrl +alt will remove masking)
:small_blue_diamond:Holding the tilde (<b>~</b>) key will allow you to scroll the canvas. This is very important function when creating seamless textures.
Pressing ctrl+n will clear the current layer
Pressing ctrl+f will fill the current layer with the currently selected color or texure
Pressing ctrl+b will “Bake” the layer
Pressing Esc or (Command+’.’ On the Mac) will abort the in-progress BEST RENDER action.
q w e r are hotkeys for DRAW MOVE SCALE and ROTATE transform modes (the left to right order of the buttons is the same as the hotkeys)
‘t’ Enters/Exits edit mode.
-Pixolator