Geniatech has completely lost interest in EyeTV. The software hasn’t been updated for nearly 5 years now. I’d be astonished if there was ever another update.
Instead, I expect that at some point in the future, a MacOS update will break EyeTV4 completely and that will be that.
I have contacted Geniatech a few times with technical questions but in recent years they have never responded. The most recent time I raised a case and they actually responded was in 2018. So unfortunately you are probably wasting your time contacting Geniatech. For all we know, it is a black hole and no-one there ever reads emails.
The only bit of Geniatech that still works is the online software ordering and payment form - which is all automated. At least that worked last year when I bought EyeTV4 and got the activation key for it, since I finally got a new Mac that could not run EyeTV 3.
Regarding the EPG, I do not use a third party EPG, I only use the over-the-air DVB-T guide which updates just fine.
I don’t think there was an intermediate build 8530.