Here's a list of the steps I used to set up my new PiCap. Hopefully this helps someone new to this like I am. I found it extremely simple and I am no where near an expert in pixels. Anyone feel free to add to this or correct me if doesn't look right. This is basically the order I used and it's assumed you have the FPP up and running successfully. Also, I set this up on a new Pi and had no sequences loaded or outputs named.
The PiCap arrived with a battery for the RTC, the connectors for power and outputs, standoffs with screws to mount to the Pi, and all the jumpers required.
1. Power down the Pi if it is running
2. Install battery into the slot with + facing up.
3. Install PiCap to the Pi's gpio pins.
4. Install standoffs and screws.
At this point, decide the power options you need. There are 6 pins with jumpers below the gpio pins and to right of the 2 amp fuse. The first 2 pins below the gpio pins power the Pi from the PiCap so you don't need a wall wart(very handy) so install a jumper there to power the Pi. The next 4 pins below that are for the power supply voltage being used. Jump pin 1 & 2 and also 3 & 4 if you are using a 7-24volts supply(the PiCap regulates the voltage required to power the Pi) or jump pins 2 & 3 if you are using a 5volt power supply(This is what I used because I have 5volt pixels).
5. Attach wires from the power supply + and - to the 2 position connector and plug it in(+ and - are labeled on the PiCap).
6. Attach pixels to the outputs. V+, data, and gnd to corresponding leads on the pixels(PiCap can run up to 800 pixels per output with power injection).
7. Place the 3 jumpers above the rj45 jack where you need them(DMX, LOR or Renard).
8. Plug in the power supply and your Pi will start booting and a green light will come on on the PiCap.
9. Once booted, bring up the FPP UI and go to the "Input/Output Setup" tab and select "channel outputs."
10. In the channel outputs menu you will see 4 options, choose "other."
11. Hit the add button and under "select type" choose "RPIWS281X." Here you can enter the amount of pixels per output and the channel start and channel count. I used a string of 50 pixels so I entered 50 pixels on channel 1 and a start channel of "1" and "150" for channel count.
12.Check the box under "Act" and click the "save" button.
13. Reboot the FPP using the button towards the bottom of the page.
14. Once the FPP is back up, select the "status/control menu" and select "display testing."
15. Under channel range I used "1" for start and "150" for end.
16. Click "enable test mode" and scroll down to RGB patterns and hopefully you have lights like I did!
Good Luck,
Todd