You should be able to implement this yourself. The ‘commands’ you have listed in your screenshot are just references that are created under Displays > Commands. Now you have to actually assign a command string for the OS type under the display settings. If you go to Display Settings > [any object] > Edit > Commands, here you can create actual command strings for the OS to run when the referenced command is used through Xibo.
The display you referenced (Philips 10BDL3051T), according to Phillips documentation, you can only control the LED’s via Ethernet or RS232. In theory, if you dig through the below documents and find the command strings to control the LEDs, you should be able to create a string that will send the command from whatever device is your Xibo player to the screen over the network and change the LEDs on the fly.
(if xibo staff reads this, I think it would be a better idea to keep the actual command strings under the Displays > Commands tab, but add a drop-down menu or something to specify what command string relates to what OS, that way commands are all kept in a single place vs per display setting profile)
The problem is not to run the command, we can already switch on the LED and change color. What we want it to switch the color based on the status (free / used) of the room. In the Calendar Module you have already templates for current events. Now I need to run the command in this template.