A JP1 cable is a good investment for almost anyone trying to customize these remotes for himself. If you're customizing these remotes for other people, you should consider a JP1 cable a necessity.

Maybe someone who knows something about a White Westinghouse DVD will answer. Maybe not. (I never heard of it before and I don't see it mentioned in the RC archives nor the JP1 group.)

With an OFA or RS learning remote and a JP1 cable, you could learn one signal from the original remote and download to your PC and have IR.EXE decode it. Then any JP1 expert (regardless of knowing nothing about White Westinghouse) could tell you which built in setup code, if any, will support it. Or maybe tell you which common (under some other name) DVD it matches, so you could load (via) JP1 an upgrade that someone else already created.

If that doesn't work, you can learn and download all the signals (in batches if they don't fit all at once in the remote) and create your own upgrade.