Problems to Change DVD Color Subtitles

I bought 2 original dvd’s and wanna make some security back up of them.

But in that back up I wanna change subtitle colors about one of that dvd’s.

eg: DVD # 1 has yellow subtitles and DVD # 2 has white subtitles. I want to change the color subtitle from DVD # 2 to became the same as yellow one like DVD # 1.

How can I do that?

I try use PGCEdit, importing the colors from DVD # 1 to DVD # 2, in my HD. But the colors didn’t change how I expect: the colors are different, despite I import exactly the same parameters from DVD #1 to DVD 2?

I really wanna know how to import / export such kind of subtitle colors between different dvd’s, because in some authoring projects I really appreciate the original studio dvd color palletes ( concerning about subtitles ) and I want to reproduce them identical in my personal back ups and projects later.

Any clue and help about the subject are welcome.

Best regards.