The confidence intervals are mostly described in Alan Agresti's CDA book.
How to calculate the intervals in other software is described at the webpage for CDA and in Alan Agresti's ICDA book, which 3rd edition will be published in 2018.
To post feature requests or ask for help, try the PropCIs Issue Tracker.
To install the development version of the PropCIs package, it is easiest to use the devtools package:
install.packages("devtools") # if needed..
devtools::install_github("shearer/PropCIs")
library(PropCIs)