There is an HQP thread on the Roon Forum. Lots of helpful information. Jussi (Mr.HQP) is a frequent participant and he answers questions directly if you PM him. I started on the HQP path at the recommendation of Tom Caufield who is the mastering engineer for Channel Classics. I was particularly interested in mch files (typically 5.0 or 5.1) which Channel provides on the SACDs and digital downloads (Native DSD is the website they own for all DSD downloads). He recommended using a separate, powerful computer to upsample the DSD64 files to DSD256 so that my multichannel DAC would not be overburdened in doing the upsampling internally. So I did that with a purpose built computer that my computer person built for me back in 2018. He contacted Jussi and worked through all the necessary details, including testing everything out This took a lot of horsepower since I am upconverting six channels simultaneously. Since I got my computer, there are more powerful and cheaper chips available. Cheap compared with lots of audiophile equipment. My main processor is an i7-6950X. It was $1650 when I got it. Today, many very powerful chips are much, much less expensive.
Larry
Larry