Oh boy, I've been here. I've been meaning to make a video on how to solve this because it is easier showing than typing.
On your PanelView Plus, delete the RSLinx Enterprise setup (restore default). This will allow you to download again, after you fix your application, described below:
In your application, right click on FactoryTalk Linx and delete the server (one level above Communication Setup). Then right click on the 2nd item in the tree (it will have your application name) and add a new FTL server. Re-create your shortcut. Re-download your application.
I tried to get RA to add how to actually fix the application to their technote, which only describes how to temporarily "fix" the PanelView, to allow another download. If the application is not fixed, then you are in the same boat after the very next download.