This repository holds the design sources for a custom PCB and plate for the cycle 7 by TKD. I ordered a prototype and got that working but I do not guarantee anything.
Note that I used a 12 MHz oscillator instead of an 8 MHz which would be QMKs default frequency for the STM32F401. That is no problem, but requires a little extra configuration. If you don't fancy that, change the oscillator circuit to 8 MHz.
Also the design replaces the standard 6.25u spacebar with a 1.25u key, a 2.75u key and a 2.25u key (in this order from the left). Very few keycap sets come with a 1.25 spacebar key, so you might want to change the design to use a different spacebar configuration. If you do that you also need to adjust the plate. If you plan to use the original plate of the cycle 7 you need to change the pcb design to a default 6.25u spacebar.
Why make my own pcb for the cycle 7? Bootloader on TKD's PCB is shit does not comply with my requirements. Also the firmware is proprietary.
What about this PCB? Sources are here and free to use however you want. However use at your own risk, I do not guarantee any of this to be functional The QMK configuration for the keyboard is available at zegonix/zegonix-qmk-configs/zegonix/cycle7. Follow the steps described in the readme file to link the folder into your local qmk repository and build the firmware.