I have an arduino robot that I control from a RPI. A future project isto connect the RPI camera, and the pantilthat, so that I could control it. With RPi-Cam-Web-Interface, what web server did you use? apache, nginx, ? I understand that I have to install the web server software before RPi-Cam-Web-Interface.
I have had several iterations with different versions of the RPi and found using nginx easiest to deal with but that is a personal preference. My current version has the Rpi3B on the tracked cambot with a Piborg motor controller and their ultraborg hat for easy use of ultrasonic sensors topped off with the pantilthat. Part of the setup is using flask. Control is via wifi using a custom webpage which takes the Rpi-Cam-Web-Interface streamed image and has pan, tilt, forward & back buttons and sliders around and below it in an ergonomic (ish) layout. The code on the RPi includes halts if the sensors detect near obstructions. I can also use a vnc connection to access the controls. Takes a while to integrate the components but worth the effort.
If you have a clean installation the RPi-Cam-Web-Interface installer will ask you which webserver you want and also which version of php and install the necessary elements for you.
The most difficulty I had was setting it up to write snapshot images and video clips to a NAS drive on the network.
Good Luck!!