The PI is a small, linux based computer. small power draw. Typically runs headless (no monitor). You can control the PI through a command shell from any other computer (if you have network capability on the PI... either wifi or hardwired network). The PI does have an HDMI output, so you can hook up a monitor if necessary (i.e. network disabled on the PI). Supports standard USB devices for mouse and keyboard (I have a logitech wireless keyboard with mouse embedded).
It will not run the LOR software since I believe that is windows based. The application that most (probably ALL) people run is the Falcon Pi Player (FPP) (You are not allowed to view links.
Register or
Login). This is a scheduling/management app that runs on the PI. Your sequences will need to be converted to the FPP format. The xLights/Nutcracker app can perform that conversion for you.
So in general, you can continue to sequence in LOR's app, use xLights to convert to FPP format (I think they are .fseq files), upload to the PI, setup your hardware configuration in FPP (tell FPP what protocol, channels, etc), schedule and run. The FPP is web based, so if your PI is connected to network (which it really should be to ensure clock is kept in sync) you can connect to the PI via a standard browser on other laptop, smartphone, tablet, etc. The lynx dongle/dmx dongle just connects to an available USB port
Audio out can be accomplished in two manners. The PI has a standard 3.5mm jack or you can use a USB sound card. From what I've read, when using the 3.5mm jack it is best to send it through some processor (typically a $50 sound processing device) before sending the sound to the FM xmitter (I believe there is a impedance mismatch between the PI and the FM02... this may not be the case for other xmitters). I use a USB sound card... plugged it in, told FPP to use that card instead of the default card and bam... music broadcasting out.
The setup of FPP is extremely simple. Takes about 3 hours to download, install and configure. My old show computer crashed the day before Halloween. I spent Friday night configuring my PI and was up and running Saturday morning, hours before Halloween.
What you normally need to run the PI as a show computer (general prices)...
Raspberry PI $35-40 with power adapter
USB hub (powered) $10-15 (may not be necessary if you run the B model w/ 4 USB ports and your number of peripherals)
min 8GB SD card (this is what holds the operating system and FPP that allows the PI to boot) <$20
min 8GB USB flash drive (this holds your show contents... sequences, audio, etc) <$20
USB keyboard $19 for the logitech keyboard w/ trackpad (not completely necessary if you have another computer to connect into the PI with)
USB wifi dongle $10
USB sound card or sound processor $50 (this may not be necessary if you don't have FM02)
Hope this makes sense... I just recently did this and HIGHLY recommend. Others can chime in if what I said above is incorrect.