Over-simplified steps:
1) burning the original ISO into USB, boot it and install Snakeoil into msata SSD as usual (the NVMe SSD won't be seen as no NVMe driver in that original kernel);
2) after successfully installed and run Snakeoil, then patching with latest original FW 1st, and then reboot and patch with the new NAS FW. If one skipped patching the latest original FW, one can't save changing to NAS kernel after patching the NAS FW;
3) After rebooting there is still no NVMe shown in "Music Libary", because one needs to ssh to partition, format and mount that NVMe in /etc/fstab for future startup-auto-mount, and etc......
4) Deselecting all players, LMS, SMB Windows File Sharing, Console login, avahi-daemon, and etc but choose Minimserver in "Snakeoil" tab, enabling Minimserver in "Music Player" tab (if can't see it then reboot again 1st), then either config Minimserver in SSH,(such as content directory), or in Minimwatch installed in other PC/platform; ......
5) Now the NVMe SSD is solely for storing music files, the OS is located in msata. So in future I don't have to spend so much time to copy all those music files if there is anything goes wrong after I make any mistake to the OS..........
Well.... I think maybe that's all.
Suggestion:
1) of course more automation by system to save ssh work will be great, but I understand that's quite an unreasonable request;
2) I think RAM disk and related file manager can be trimmed in NAS FW. I'm sorry that I think I'm one of the guy suggested to add RAM disk in Snakeoil....... sorry! :shy: