The published OCX Schema

The definition of a grid spacing group for a sequence of grid positions with equal spacing ZSpacingGroup has the following child elements:

Child	Namespace	Type	Use	Cardinality	Choice	Description
Description	ocx	xs:string	opt.	[0, 1]	False	Contains a description of the component its parent represents. The description is stored as a string. You can use this element for whatever purposes you require. This element can be used inside many OCX XML elements but is optional.
GridPosition	ocx	ocx:Quantity_T	req.	[1, ∞]	True	The location of the first grid position in the spacing group.
Spacing	ocx	ocx:Quantity_T	req.	[1, ∞]	True	The grid spacing of the spacing group

ZSpacingGroup has the following attributes:

Attribute	Namespace	Type	Use	Description
firstGridNumber	ocx	xs:integer	req.	The first grid number in this group
count	ocx	xs:integer	req.	Number of repeated grid spacings
name	ocx	xs:string	opt.	An optional descriptive or display name.
id	ocx	xs:ID	req.	An identifier for an element unique within the scope of the XML file. Each id must be unique within a document. The attribute uses the standard XML 1.0 ID type as defined in the XML Schema specification. This attribute is required in many OCX XML elements and an application should generate them automatically.