Mini-PCIe to dual-channel SATA adapter (Do not attempt if there are problems).

Background:
I bought an industrial control board to build a Synology NAS. Since the motherboard only has one SATA interface, I wanted to expand the unused mini-PCIe interface into a SATA port.
There are many ready-made boards available online, some as low as 20 RMB with free shipping on Xianyu (a second-hand marketplace). Although buying directly is more convenient, I wanted to practice designing the circuit myself, even though I'm not an expert, I wanted to challenge myself.
 
Design:
I searched for a lot of information online, but there wasn't much on this topic. I chose the relatively inexpensive ASM1061 solution, drawing and routing the circuit based on the schematics I found, with the layout largely referencing existing finished products. All the reference materials I found are attached.
 
Usage:
I tested it on a PE system and it recognized and tested normally. The results are shown in the image below:
1. A 500GB 3.5-inch Western Digital mechanical blue hard drive (purchased from Xianyu for 17 RMB);
 
 
2. A 2.5-inch 240GB Western Digital solid-state green hard drive (removed from an old laptop).
 
Summary: I don't know much about computers, so the read and write speeds are pretty average. It could be a problem with the hard drive itself, or it could be a problem with my PCB layout. For me, as long as it works, it's fine. I also hope an expert can help modify the PCB and
 
program the firmware:
I need to use a programmer like the CH341A Gold to program the flash chip. After programming, I can use it directly in the PE system.
 
I suggest soldering the chip onto the board after programming, otherwise the board may not detect the chip. There are tons of tutorials online about programming, and the seller will also provide you with a tutorial when you buy the programmer. I will also include the firmware in the attachment.
I found the firmware from this website, which also contains driver installation instructions for various systems. It includes the latest Asmedia ASM1061 4.27V2 firmware and Win10 driver.
 
 
My configuration: Note that it must match the flash chip model used.
 
PCB requirements:
1mm board thickness ,
impedance matching required
 
. Note:
The chip gets hot during use, so I added a heatsink. I also rearranged the PCB layout, creating a window on the back of the chip for better heat dissipation. The PCB file is included in the project files.
However, it hasn't been tested yet, but it should work normally.
 
 
 
 
Finished product photos:
front
 
and back
of the device.