Is there any reason why this pattern shouldn’t be railroaded?
No. It is perfectly fine to railroad.

Can I make the valance all one piece instead of making the jabots separate?
Yes. You can make the valance all one piece.

Do you recommend using interlining in this valance?
Interlining is a good thing if the fabric is light weight or needs body. However, I would hesitate to have it in the rod pocket two times, which is what will happen if you use it for both front and back sections. Eliminate the interlining in (at least) the back valance rod pocket.

After purchasing the pattern, I discovered that all views shown in the picture were printed together as an overlay pattern. I like to reuse my patterns for more than one customer, but the way this pattern was printed, only one view could be used which means if I have another customer that requests a different view, I would have to purchase yet another pattern, I don’t feel like I got my money’s worth out of this pattern. In the future, please print all views of the pattern separately so they can be reused.
If we did you would have to purchase the pattern several times to get what we give you in one package. Most workrooms make a complete pattern of each size and view using a sturdy fabric or butcher paper. They keep these patterns to reuse.