Word automation fails

This is not a solution, but...

I have proceeded to change the declarations of the variables, as follows:

Before:

Friend WithEvents oWord As Word.Application
Friend WithEvents oDoc As Document

Now:

Friend WithEvents oWord As Object
Friend WithEvents oDoc As Object

In the same way, I've modified the word and document application mapping code, as follows:

Before:

oWord = CreateObject("Word.Application")
oWord.Visible = True
oDoc = oWord.Documents.Open(Trim(Main.docName.Text), varMissing, varMissing,
varMissing, varMissing, varMissing, varMissing, varMissing,
varMissing, varMissing, varMissing, varMissing, varMissing,
varMissing, varMissing, varMissing)

Now:

oword = ctype(createobject("word.application"), microsoft.office.interop.word.application)
oDoc = CType(oWord.Documents.Open(Main.docName.Text, varMissing, varMissing,
varMissing, varMissing, varMissing, varMissing, varMissing,
varMissing, varMissing, varMissing, varMissing, varMissing,
varMissing, varMissing, varMissing), Microsoft.Office.Interop.Word.Document)

with the result that it works. But with the change I lost the ability to handle the "DocumentBeforeClose" event, which prevented the document from being closed outside the control of the application.

Additionally, the following code, (which previously did not produce any error)

rngParagraphs = oWord.ActiveDocument.Range(Start:=oWord.ActiveDocument.Paragraphs(1). Range.Start, End:=oWord.ActiveDocument.Paragraphs(oWord.ActiveDocument.Paragraphs.Count). Range.End)

causes the "Count is read-only" error.

But replacing it with:

Dim nParg As Single = oWord.ActiveDocument.Paragraphs.Count
rngParagraphs = oWord.ActiveDocument.Range(Start:=oWord.ActiveDocument.Paragraphs(1). Range.Start, End:=oWord.ActiveDocument.Paragraphs(nParg). Range.End)

or what is the same, substituting .Activedocument.Paragraphs.Count for a variable in which the content has previously been loaded, works perfectly, which perplexes me.

He said that this is not a solution, just a palliative with problems. But I wanted to close the consultation with some more information.