John,
Since ClearOS is a ghost ship at the moment there is no way for me, as an outsider, to release an updated Serviio package since I need someone on the inside to get the build environment up and running and also to release the package into the ClearOS repos. So you are on your own.

If you want you can build a new rpm package yourself. I do not think there are any major changes in the serviio source files, so most of it will likely compile OK without to many changes (you might need to adjust one or two of the patch files). If you have never done this it will probably take you a few hours. Below follows a brief instruction (from the top of my head, which means that I might have forgotten something...) of what is needed:

1. I suggest you create a virtual machine on your normal PC to use as your development environment (VirtualBox is one alternative if you are using a Windows PC). Create a Linux 64 bit machine. (set the "network card" to run in bridge mode (not NAT), so that you can connect to it from a ssh terminal on your LAN). Download the ClearOS 7 DVD iso file to install ClearOS as the operating system on your virtual machine.
2. When your ClearOS virtual machine is up and running, use ssh from your PC to connect to it (puTTy is a very good program)
3. Follow the instructions here to "upgrade your virtual ClearOS machine so that it has all needed files to build rpms": If you have not used vim before for text editing, you can skip that part and maybe use nano instead, which I think is easier.
4. Now you should have a folder called "rpm" in your home directory for your normal user (do NOT build stuff logged in as root).
5. In your home directory create a folder called serviio. download the old source-rpm file:
6. Unpack the source rpm: You should now have 2 folders:
SPECS
here your serviio.spec file should be

SOURCES
here the rest of the files should be

7. You will likely need to download a few more files: The files listed in "sources.download" should be downloaded and put in the SOURCES folder. (use nano to open the sources.download file, there is one file on each row (ignore the sha256 checksum in the beginning of each line, but look at the url to the right). The file "sources.download" is not needed in the building process.
8. edit the serviio.spec file in the SPECS folder with your favorite text editor. change the release version etc so that it matches the new serviio release rpm name/version. Save the file
9. Copy both the SOURCES and SPECS folders with its content to the rpm folder
10. go to the SPECS folder and try to build
11. You might be missing a few packages, in such case you will get an error stating what is missing. Using your root account install the missing packages . Repeat step 10-11 until it starts building.
12. You might also get an error that one of the patch files could not be applied. In that case the upstream (serviio) source files have changed so much so that the patch files needs to be adjusted. Google to find out how to create/modify patch files (tip: create two folders "org" and "mod", unpack the files to be patched from the serviio rpm and put them (with the correct folder tree) under the "org" folder. Copy the content of the "org" folder to the "mod" folder, edit the files under the "mod" folder (according to what you can see in the old patch files). Then use something like this. Then try to build again.
13. After a successful buld, copy the rpm file (found under rpm/rpms/...) to your machine where you want to install serviio. You can try in your virtual development machine first if you like.

/Fred