The novelty of having a telemetry overlay on my videos wore off so I rarely do it. But it should still work.
Walking you through the process in any given program is too much for here, this is the principal.
Take the length of your flight video, hypothetically we'll say it's 10 minutes long, make a video (I used Final Cut for this) that same length, but only 1080p. That video will do nothing but be a solid green video.
Take the 10 minute, 1080p, green video and use that in Dashware. Use your real flights telemetry file to make the gauges on top of the green video. Keep in mind that you'll likely be stretching the gauges 2x on both axis later on, so graphically intensive gauges will look pretty mushy.
Export your video for Dashware. You'll now have a 10 minute, 1080p video that's nothing but green and gauges.
In Final Cut (or whatever video editing software you use) take your real flight video and put it under your green gauge video. Use the green-screen feature of your video ending app to subtract the green. This will leave your gauges visible on top of your flight video.
You can stretch the green video from 1080p to 4K if you want. Or you can leave them as they are (1/4 scale). The smaller version will be sharper.
Once you learn the basic workflow it's not too hard. I kept re-using the same 20 minute green video source in Dashware. If you design your gauges 4x the size you want them in Dadhware, then you can overlay them at 1/4 on your 4K to keep them 1:1 pixel scale.