Regarding WORDSNET-16121, it is to update you that we use some combination of default system classes to get correct URI in output PDF document. In your example:
string escapedUri = System.Uri.EscapeUriString(@"https://www.test.com/Test/12345/Abc/Test.html?testPath=/Test test");
This code would produce “https://www.test.com/Test/12345/Abc/Test.html?testPath=/Test%20test” string. So current implementation in Aspose.Words seems to be correct.
If you are sure that your way of escaping URI string is correct, we can add an option DoNotEscapeUri in PdfSaveOptions. If this option is enabled we will skip process of escaping and write value of URI from the source document. So, it will be up to you to properly handle all possible cases.
Please let us know if addition of this new option in API is acceptable for you?