I have installed plex app just to try other DLNA server. as I don;t like it I have reused it’s start.sh script to start Twonky instead of Plex.
Location of the public folder(where are your shares and Apps) are here /mnt/HD/HD_a2/Nas_Prog/
inside plexmediaserver I have hashed(#) all lines and added just one line
/mnt/HD/HD_a2/Nas_Prog/plexmediaserver/twonky/twonkystarter -appdata /mnt/HD/HD_a2/Nas_Prog/plexmediaserver/twonky/appdata &
Full folder location to Twonky and making this location also destination of all config files (not to lose anything after restart).
after these steps Twonky needs to be configured using :9000 port but this is easy. Licence will be needed after 30 days.
PS.
How to install APP topic - WD MyCloud Gen2 - Enable apps install tab + Apps!
Twonky download location - Twonky WWW