Update for Roon in Docker: audiolaz Room 1.3, out yesterday, can now install the filter into Roon running in a Docker container on a Synology NAS, in one step.
In the app, connect to your Roon Server with the NAS's administrator account (DSM refuses root): the app finds the Roon container by itself, asks for that account's password once (it is never kept), writes the filter and restarts Roon (about 40 s, the screen says so). SSH must be enabled on the NAS (Control Panel › Terminal & SNMP).
It is new and was tested on a simulated NAS, so please tell us here how it goes on yours. Loading the file by hand in Roon (MUSE › Convolution) still works, with exactly the same filter.