[QUESTION] - How to correctly configure import of namespaces in OML2OWL tool?

[kataph]

I am trying to translate from OML to OWL this ontology: https://github.com/OpenModelica/ModelicaOML/

When trying to use the owl-adapter tool various errors are returned e.g.

        [1, 2]: Couldn't resolve reference to AnnotationProperty 'dc:title'.
        [15, 9]: Couldn't resolve reference to Scalar 'xsd:string'.
        [21, 9]: Couldn't resolve reference to Scalar 'xsd:string'.
        [65, 9]: Couldn't resolve reference to Scalar 'xsd:string'.
        [73, 9]: Couldn't resolve reference to Scalar 'xsd:string'.
        [78, 9]: Couldn't resolve reference to Scalar 'xsd:string'.
        [83, 9]: Couldn't resolve reference to Scalar 'xsd:decimal'.
        [116, 9]: Couldn't resolve reference to Scalar 'rdfs:Literal'.

etc., which suggest an issue with the import of the corresponding namespaces.
Following the discussion in issue 67, I've tried to set up the structure of the project in such a way that files containing the needed namespaces are located in relative paths that reflect their URIs.
In particular, the (input) project structure is

|...
|catalog.xml
|
|src
--|standards
   | --|...
   |    |purl.org
   |     --|dc
   |         --|terms.ttl
--|main
    --|oml2
        --|openmodelica.org
            --|openmodelica
                --|bundle.oml
                   |classes.oml
                   |modelica.oml

The file catalogue contains

<?xml version='1.0'?>
<catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog" prefer="public">
	<rewriteURI uriStartString="http://openmodelica.org/" rewritePrefix="src/main/oml2/openmodelica.org/"/>
	<rewriteURI uriStartString="http://" rewritePrefix="src/standards/" />
</catalog>

And the various .oml files all import the :dc prefix as extends <http://purl.org/dc/terms/> as dc (idem for xsd and rdfs, but lets focus on dc only), and the term.ttl file contains

@prefix dc: <http://purl.org/dc/terms/> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .

dc:title a owl:AnnotationProperty .

Nevertheless, the error 1, 2]: Couldn't resolve reference to AnnotationProperty 'dc:title' persists.
Am I doing something wrong?

Many thanks for the kind attention