Edit image from LR either by plug-in to DeN or DeN opened first, and then edit from LR

I discovered 2 things.

  1. when working from LR with DeN as plug-in I only have the option to “Apply” changes to the “TIFF” file from LR.
  2. if DeN is opened and minimized first, then I go from LR right click > edit > DeN, then I get the option to save as another file format, but this is not starting with a RAW file.
    Why isn’t this mentioned anywhere in the tutorials?