Question

I would like to be able to record 8 channels at a time and have them show up in Studio One v4 or v5 as separate tracks to be mixed later...

Answer 1

Using Studio One Artist or Professional using the Tascam ASIO driver on Windows or Core Audio on Mac you will see all inputs.

If you use Studio One 4 / 5 Prime (the free version) only 2 inputs will be available, upgrading to Artist or Professional will open up all the inputs on your interface as you are asking.