VST instruments don't get track MIDI

I fired up Cubase for the first time in quite a while, wanting to noodle around. I’m running Windows 10 64-bit on a Core i7 8700K with 32 GB of RAM. I created a new blank project.
A few configurations have changed since I last used it, so I configured the default low-latency ASIO driver, plugged in my spare Korg MicroKey, and set it up in the MIDI panel, added a Komplete VST, and tried to play.
Nothing.

I can see MIDI coming in in the Transport panel. I can record MIDI to the Instrument track. But the MIDI on the instrument track, doesn’t make it to the VST.

If I quit Cubase and just start a Komplete instrument, it plays fine, using the same Audio / Midi setup.

Interestingly, I can play the first instrument I add after I start Cubase and add the project, while it’s first on the screen after selecting “add instrument.” Once I “accept” the instrument and create a track, it stops making noise.
This happens for Absynth, Massive, and FM8, so I’m pretty sure it’s not instrument specific.
Also, even while playing back the recorded MIDI on an instrument track (or notes entered while double-clicking the part,) I don’t see MIDI in the instrument, and for the instruments that display “polyphony,” it stays at zero, so it seems as if the connection between Cubase and VST instrument is somehow severed.

The built-in “screen keyboard” shows the same problem.
Also, the Transport panel does not play the click when enabled, no matter whether playing back or recording. Might be related?

Really wild guess; Maybe MIDI routing is dependent on ASIO pumping its thread, and somehow this works while inserting the first instrument, but seizes up after the first track is created? That would explain the click being silent, too.

FWIW, my solution was to upgrade to Cubase Pro 10. Not happy that I had to, but it is what it is.
That being said – I’m now having eLicenser issues with that upgrade.
Why do I have to spend the few hours I have for music, on shitty software bugs, not on playing?

Because you chose to use a computer, certainly because it offers you a lot of possibilities you couldn´t get otherwise.

[quote[Because you chose to use a computer[/quote]

I’m a professional software developer. I know that software development is hard. But this is not a software failure, this is a product management failure.