Depending upon where you downloaded it from, a note went out stating you needed Acrobat 8 or greater.
Due to the desire to preserve the character sheets as form fillable, there was no way to merge the separate PDFs together, so I used a little used technique (at least by me) of creating an Adobe Package that brings them all together in, as you stated, a portfolio style.
The fancy parchment stands for now, as I don't know the secret techniques of the layer- that's my layout guy's role. I put these together, but it's on my to-do list to learn how to do. Putting this thing together took some hours, as I had to fiddle with learning the nuances of the Adobe Package--this was my first go with it.
As Wolverine noted, it's probably easiest to pull 'em into another document. I wanted them to look pretty, but I will
learn the secret. I just have to catch up on my writing first. You guys do want me to write more, don't you?