Have you read the OSPi user manual? If not, it might help with all of the confusion. It is available here:
https://opensprinkler.freshdesk.com/support/solutions/folders/5000149652
That link also has two other articles:
- Creation of SD image preinstalled with the Unified firmware you already installed
- Updating or removing the Unified firmware
To answer your immediate question, the default port is 8080 and the default password is opendoor. Please note if you use the app instead of just the API, the password will instead be hashed (not clear text).