It sounds like you're not using the right software with it. Try the ES-8 with either Expert Sleepers' Silent Way (Windows) or MOTU's Volta (Mac) as a gateway/translator. The ES-8 is designed for that sort of software, something that can send a signal to a DC-coupled audio interface (which is what the ES-8 is) and the module converts that into the proper CV/gate/trig calls on its end. Even with a plugin like Reaktor, you're still going to need to use something of that sort that knows how to address the ES-8 properly.