When you installed the iGrid demo, a comprehensive help file for the iGrid OCX in the CHM format was installed too. Its file name is iGrid500_10Tec.chm, and you can find it next to the OCX file (iGrid500_10Tec.ocx). If you used the default settings while installing the iGrid demo, the OCX and CHM files are placed in the following directory:
C:\10Tec\iGrid ActiveX 5.0\OCXs_and_Help\
In addition to that, you can always browse the list of available iGrid memebrs with short descriptions in the VBA Object Browser (F2).