Hi,
I've nearly the same laptop (HP Spectre x360), the only difference is a 2k touch display and a 512GB SSD.
Everything is working well (including touch screen, trackpad, keyboard, sound).. I've taken the Clover files in this topic,
the only issue is the internal display.
I get blackscreen, if I want to start from the SSD.
If I plug my external display, everything is working fine, but the internal is still black.
The Display is detected in "about this Mac" as "Built-in Display, 15,5 inch (1920 x 1080) UHD Graphics 620 1536MB".
I'm at my wits end at this point.
I'm very grateful for any help.