This is hopefully not a repost of the many other error code 191 messages out there.
Heres the issue, I am using the dialog ui feature on our site, but the app has been built by a third party. This third party has their own domain and so do I and therefore the app domain in the third parties fb application is making reference to their own domain. Is there any possibility that the third parties fb application can be shared. My instance is web based as is theirs? Do we need to reference seperate apps in order to make this share dialog I am working on work?
Yes, since you want to use their code on a different domain, then you will need a new App Id and secret with their own settings to point to the new location of the code.