Let me save you countless hours of wasted time by sharing my findings after being in exactly the same situation.
Was using PCNVR4200 very happily for several years in spite of it no longer being supported.
I added an 8MP 2CD2385FWD-I to my setup and found that the only way to get it record and display was to limit the video stream bitrate to 4096. Any higher and PCVNR4200 won't display or record the stream. Add to that, H.265 is not supported so you are limited to H.264 encoding.
The problem with 4096 bit rate for streaming was that there was a lot of artifacts and pixilation on fast moving objects and without H.265 encoding, a huge amount of storage was needed.
I tried the following free apps.
1.
BlueIris - I didn't like it (everyone has different experiences).
2. Milestone Xprotect - Initially, I didn't like it but over a short period of time I came to understand its interface and found it very easy to use. Really liked the remote Web Interface. Only problem was that it needed up to date PC hardware and recent Nvidia graphics card to support H.265 steams. The cost of building even a basic PC with the necessary specs was going to be in the $400-$500 range.
3. Hikvision - HikCentral - Found out that it is only management software and has no recording function.
After weighing up the pros and cons I ended up settling on a Hikvision NVR. From Ebay a 7608NI-I2/8P was only AU$350.
The NVR just works, supports all current Hikvision cameras. Is well supported by Hikvision and is relatively trouble free. Supports H.265+, H.264 and third party IP cams. Does on the fly transcoding for remote playback.
If you want free, I'd suggest Milestone Xprotect +. If you already have a properly spec'd PC it would be my choice.
If you need to spend money on hardware to upgrade or build a PC, then go for a dedicated Hikvision NVR.