In regard to #2, I'm just talking theory here, but this is how I would pursue it.
Based on what you are saying, it sounds like you need a DYNAMIC dashboard - one that changes based on who accesses it. That is going to require scripting of some sort. And since Revu doesn't support (at least that I have found) the ability to SHOW and HIDE markups, etc, then simply hiding things you don't want a contractor to have access to won't work. You could script LOCK/UNLOCK - but I think the user could over ride that while using. Just depends on how secure you need to be. I think you will have to create a solution using FORMS. The two options I would explore are:
1 - Create separate dashboards for each contractor. For the DEFAULT document that opens, instead of any one dashboard, I'd create a PDF that has a form field that is auto-populated by the username (for verification purposes by the user). You could even add a password field here if you like. Add an OK and CANCEL button and you have essentially created a LOGIN SPLASH SCREEN. Then with Javascript, based on the username (and password if used) when the OK button is pushed the user is taken to "their" dashboard. Advantage: Minimal scripting. Disadvantage: Maintaining multiple dashboards for multiple contractors/users.
OR
2 - Create a single dynamic dashboard using forms and Javascript. Use Javascript to change / auto-populate the contents of popup fields based on who "logs in". When the user opens Revu, Javascript captures the username and, in essence, creates parts of the dashboard on the fly. Buttons are created (and I think form items CAN be hidden, or "deactivated") and so on. You would have to script not just parts of the interface, but script the scripts used by the interface as well. Advantage: Just one dashboard. Disadvantage: A TON of Javascript programming.
That said, this is again - all theory. I'm not a Javascript person and am only remotely familiar with Revu's form features as we don't use them here where I work (yet). There are lots of Javascript resources on the web. Here is one I found on capturing a Windows username for a PDF file:
https://forums.adobe.com/thread/827805Good luck!