I have attempted to fully integrate HDHomerun into CMC, using their software development kit. While I can get it barely working, it always goes haywire after a few minutes of playback. While I would love a more integrated look and feel an integrated app, it's a pretty big showstopper if it simply doesn't work for more than a few minutes. While I might be doing something wrong, my gut tells me it's my development tools that are failing here.
With WMC, Microsoft was big enough to cajole other vendors into developing for their platform. So I don't think MS actually embedded those solutions into WMC, but rather created an ecosystem that permitted it, and was able to convince these companies to providing plug-in solutions.
Unfortunately, CMC is small potatoes compared to WMC, and even if I created a plugin system, it's doubtful any company would develop for it. That means it falls on me to try and do this myself. Beyond just the challenges of such an undertaking, these efforts detract from my ability to continue developing other aspects of CMC.
For these reasons, I have tried very hard to make CMC very good at launching other apps, instead of trying to rewrite every other app inside CMC. The external links launcher, combined with hotkeys, makes CMC a very powerful hub. If you have a true RC6 compatible remote, you can even use the advanced remote programmer to launch and interact with other apps even when CMC is not running.
Of course, you're still at the mercy of other vendors and their apps, which often are atrocious to look at and use, and many work poorly with a remote. The advanced remote programmer can help a bit with that last issue though, if you're lucky enough to have an RC6 remote and are willing to spend the time to configure it.
There are other apps that work with Hauppage tuners, and they may work better than WinTV. Here's a page listing some options:
https://alternativeto.net/software/wintv/ Whichever app you settle on, it's easy to configure CMC to launch it.
Obviously the glory days of HTPC's are behind us now. The death of WMC didn't just affect Microsoft's HTPC solution, it had ripple effects throughout the entire industry, much of which slowly transpired over the following years. For example, YouTube used to have an awesome HTPC remote optimized web page that existed for solutions like WMC, and it worked awesome with CMC, at least until that fateful day Google retired it. Now it's nearly impossible to use YouTube without a mouse or touch.
I continue to research, develop, and test workarounds and solutions, and I still have the desire to make CMC even better. But for now, it's best to get well acquainted with CMC's launcher.