Don't think that's a RH problem - sounds like an issue with your source control...
Hmmm, seems odd that they would have been removed.
Knowing how version control works, the actual content is typically in the Source Control database on the server. And there are copies on the local PC. And the copies are generally manipulated by using the read only flag.
Have you tried using the "Get Latest Version"? I think that's what it's called. I may be remembering Microsoft Visual Source Safe. But I would think RoboSource Control would offer an identical feature but maybe named slightly different.
The Get Latest Version should copy things from the Server database to the local machine. Assuming, of course, that the topics haven't been actually deleted.
Not only do I have the same problem, I am having problems where a project is pulled from the Robo Source Control server and opened fine. Close, reboot the printer and reopen the same exact project and it says it has been removed from source control, do you want to discontinue looking for the project. So far, it seems to be happening mostly with one project in particular but we are getting quite frustrated.