As long as you don't charge for the route, most creators don't mind you using their "stuff". It's pretty much covered in the third party creator's "readme" files, and in Dovetail/ RSC's EULA. But it never hurts to ask.

Of course, you also want to make sure that someone downloading your route has all the payware needed. Again, in a readme file.
You have two posts now, so you should be able to upload an attachment (instructions at the top of the main Forum page) or, like I do, I upload screen shots to my Photo Bucket account, then link to there from this Forum.
And,

. Look forward to seeing the progress on your new route! Sounds interesting.

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