Just to be sure we’re on the same page, are you talking about the simple OAI-PMH harvester described here?
If so, if the file is not being created, perhaps it is a permission problem – you might want to make sure that the user account you are using to run the import has write access to the harvest directory and any relevant subdirectories. If that’s not the problem, please let me know any error messages you are seeing and I can help investigate.
As for the second part of your note, you are correct that right now, we only have tools to import harvested MARC records. I am currently working on another simple import tool that will allow you to use XSLT to map any XML format to the Solr index. I will add this to the trunk when it is a bit more mature. If you want to see it in the meantime, I’d be happy to email you my code so far – just let me know.