Symptoms

If during the project creation or implementing custom scripts there is an issue:

System.Runtime.lnteropServices.COMException (0x80004005): Index out of range.
  at ABBYY.FIexiCapture.lFields.get_ltem(lnt32 .index)
  at Main.Execute(IMainWindow MainWindow, Object Commandld)

Cause

The issue itself is caused by the incorrect usage of the indexes.

Resolution

To solve the issue, the implemented script must be reviewed and debugged. It is possible that some conditions are incorrect and the system tries to open the unexisting line/instance that was deleted/modified by the previous action of the script.