> 2. Not sure what you mean by this, we have no _DX files?
>

I mean, You said that the C:\Program
Files\Borland\Delphi6\Projects\Bpl\IBO40CRT_D6 is not found...

I remember when i install an old version, 4.3<nn> i got error
installing and note that the <_DX> (_D5, _D6, _D7).
And other, i don't remember if the version in the conditional
compilation declaration
{$IFDEF don't remember} TIB_don't remember {$ENDIF}. the only thing
i remember is, that i'd delete some prefix and it works!
the default extension (_DX) for the last version of delphi was
declared without the _DX sufix, i wess!!! or something like it ;-)

sorry, is not the answer of your problem but is an item in your check
list, i can't found the 4.3 version folder of IBO to verify it.

if i can find it( i don't believe, my HD had several formats by year)
i'll write you again.