Now I know some of my LPA864 info

CPU m3-7Y30 is Kaby Lake "Y" 7th gen CORE M processor 4.5W TDP
It supports max of 10 PCIe lanes, on board, 6 available/used:
PCIe root-port #3: used by Intel WiFi (+ BT) module
PCIe root-port #4: Gigabit Ethernet RT8111
PCIe root-port #5 (and 6, 7, 8): M.2 M-Key (max 4 lanes and can do x4),
PCIe root-port #9 (and 10): M.2 E-Key (max 2 lanes and can do x2)

CPU Fan is very quiet.

USB ports used:
1) one USB is used by Intel (WiFi+) BT module
2) a USB 1.1 port (USB-serial) used by EXAR XR21V1410 (CDC-ACM driver aka built-in "driverless" driver), in Win10 it's detected as COM4
this is exposed on top-side of the RS232 connectors (Orange-colored dotted line block),
there is a proper RS232 driver ( -5.73V to +5.73V RS232 voltage level) on board
3) another USB port back-to-back connects to on-board Arduino Leonardo's USB port (latter emulates a COM port, detected by Win10 as COM3)
4) one more USB port exposed on Key-E M.2 slot
5) (not sure, not tested yet) stated as USB2.0 top-side, black-colored dotted line block
6) 3 USB 3.0 "type-A" female connectors

Usable UARTs:
# 2) above
As well as exposed connection leads on E-key M.2 slot

One SATA port, exposed in key-M M.2 slot.
<-- that key M slot is dual mode: SATA or PCIe (such as used by NVMe SSD) one way or another

I had tried using a $5 "key-M M.2" to "PCIe 4x adapter" in the past to connects to regular sized PCIe cards in the past.
I don't see there is any problem using the same method for LPA864.
<-- I had tested PCIe graphics card, SATA RAID card, quad-fast gigabit Ethernet card, etc. All works.

(not tested) PCM IN and OUT on E Key M.2 slot.

ccs_hello