Co2 Superctitical Extraction - Wax to Oil?

I have recently purchased a small scale co2 extraction system. I am producing very fine quality crumble, sap and shatter material finishing it off in the vacuum oven. I would like to know if anyone has experience filling the cartridges that screw on to the e-pens, how do I get my material to a liquid form that is soluble enough?

I need to add that I am NOT interested in using glycol oils to thin out my extracted product. Please advise.