Ok, I’m sorry if this isn’t exactly at the level of most people on these forums but here goes 
I’m making an SLA DLP printer with a Nema 17 stepper motor and a projector.
I’ve downloaded photonic onto my raspberry pi and can connect to he gui via google chrome, which is great.
Question 1: should my raspberry pi when I run it with a projector still show the desktop like before i ran the commands, or should it have pulled up a gui of some sort. That’s what I originally thought was going to happen before but I just wanted to double check, because right now hooking it into the projector it’s just going to a desktop
So assuming that everything is installed correctly I need to try and set up my stepper motor. I’m running an arduino uno with Grbl connected to a stepper driver A4988 PLOU into a Nema 17 motor. So from the pi my connections are: PI > Arduino > driver > motor.
Question 2: Do I need ramps to make the arduino run the stepper driver?
so if I don’t need any further hard ware my final question becomes about setting up the printer in the GUI of photonic. I selected:
simulated display (not sure what that means)
Always full screen mode (if that’s relevant idk)
GCode for the serial port
Auto detect projector (I also tried a few other settings for this one since it said it wasn’t detecting it)
After the printer is set up, I constantly get the message saying my printer isn’t started if I try to move the stepper motor.
When trying to start the printer it says it can’t determine the projector model. It’s a Benq projector that I’m currently testing with. When I don’t select a setting for the projector however it does work, however trying to move the does not work.
Question 3: What do I need to do, or what information do you need to be able to help me. I’m sorry for being an idiot but I have no clue what I’m doing