Tolerance, Decimal Places and Screen Z-Coordinate
Tolerance
Drawing > Properties > Tolerance 
HiCAD saves all coordinates with the greatest possible accuracy. Due to rounding errors, numerical values can be checked for equality except for a certain tolerance size. You can use this function to set this tolerance size.
The default value is 0.001. This means that two points are considered equal if the distance between them is less than one thousandth mm.
Decimal places
Drawing > Properties > Attr. 
> Decimal places 
Drawing > Properties > Attr. > Decimal places for angles 
When displaying values and coordinates using functions of the Information menu, you can specify the number of decimal places to which you want the coordinates to be rounded in the data store. The settings for angle value can be set separately.
The default setting for angle values is 2, for other values it is 3.
This setting, however, only applies to the current HiCAD session. To change this value permanently, open the Configuration Editor (ISDConfigEditor.exe), select ... > System settings > Miscellaneous, and change the parameters Decimal places, Coordinates or Decimal places, Angles accordingly.
Tolerances, Decimal places and Screen coordinate
Drawing > Properties > Attr. > Screen Z-coordinate 
This function is only relevant for generating and positioning general cylinders without transformation. It is used to move the screen plane by the value z. 3-D parts are then positioned from a front plane parallel to the screen plane.
(1) Construction of a general cylinder in the top view
with z=0
(2) Axometric view 2 with x-y plane
(3) Construction of the same cylinder in the top view,
but now with z=50
(4) Axometric view 2 with x-y plane
