In our case study we investigate a server for answering OWLQL queries with distinguished variables only (henceforth called OWLQL). This server acts as a proxy that delegates queries to back-end DL reasoners that manage the KB mentioned in the query. This report describes load balancing and caching strategies in order to exploit previous query results (possibly produced by different users of the local site) in the presence of incrementally answered OWL-QL queries. In addition, the effects of concurrent query executions on multiple (external) inference servers and corresponding transmissions of multiple result sets for queries are discussed.