Fix for Everything v1.5(a). Also supports v1.4 side by side.

[shanto]

1. Fix for Everything v1.5(a). Uses the new hidden window access instead of clipboard.
2. Turning off alpha_instance flag is no longer necessary. Putting it back to default helps.
3. Supports both v1.5 and v1.4. Earlier version is supported through clipboard as before.
4. Fixes a bug which crashes QuickLook when the path returned by client program is quoted.

[quantumleap-]

Personally, I strongly recommend using the Custom Open command in Everything 1.5a.
No implementation on the QuickLook side is required.

[shanto]

Personally, I strongly recommend using the Custom Open command in Everything 1.5a.

No implementation on the QuickLook side is required.

What's your recommendation for getting QuickLook follow cursor movement aka focus change?

[quantumleap-]

What's your recommendation for getting QuickLook follow cursor movement aka focus change?

Yes, that's right.
There's no way to track focus changes.
You'll need to modify your code in that case.