There isn’t any extra steps to take (other than to ensure that your scheduler is running and that there is the Indexing scheduler set to run in admin).
AOD comes bundled with the Zend Lucene implementation so it comes as part of SuiteCRM.
What permission errors are you getting exactly? Is the permissions of SuiteCRM set correctly?
I suppose the next question is do I have to install Apache SOlr to get the text in the documents indexed, or is it a planned update with this functionality coming soon?
AOD will index text in documents as is, no extra work needed (although not every document type is supported currently). There isn’t any integration with Solr but this may be something we consider in the future.