How to calculate the scores of X and Y from an OPLS model object

Question

I'm trying to learn how to use the ropls package. However, I was totally lost when reading the package's vignette. I then tried to read the package's help page (retuned from running the code ?opls in RStudio) but that didn't help much.

In particular, I want to understand how the model calculated the score matrices for predictors X and response variable Y. From the following example

data(sacurine)
attach(sacurine)
sacurine.plsda <- opls(dataMatrix, sampleMetadata[, "gender"]

I think the Y's scores can be extracted as follows

sacurine.plsda@uMN

# returned:
              p1           p2           p3
HU_011 -0.9085508 -0.248134724 -0.807150202
HU_014  1.0946395  0.910514168  0.550667721
HU_015 -0.9085508  0.167882380  0.027208109
HU_017 -0.9085508 -0.125803393  0.022100921
HU_018 -0.9085508 -0.320990409 -0.036994383
HU_019 -0.9085508 -0.525569323 -0.266313385
HU_020 -0.9085508 -0.541144344 -0.911891631
HU_021 -0.9085508 -0.296989083 -0.124188530
...

My questions are:

1. Why did the sacurine.plsda model use only one response variable (in this example gender)?

2. How were the values from sacurine.plsda@uMN calculated?