Returns a unit using its index or its name from the
from the Parameters collection.
Parameters:
iIndex
The index or the name of the unit to retrieve from
the collection of parameters.
As a numerics, this index is the rank of the unit
in the collection.
The index of the first unit in the collection is 1, and
the index of the last parameter is Count.
As a string, it is the name you assigned to the parameter using
the