We have to open every Repository / Profile so it should be non. But this is not the problem. GUI hangs sometimes during an operation. Also during backup / restore, the gui will not come back and we have to reopen it. Is there a known problem?
Interesting that you are still having the problem. As soon as 3.3 came out, I jumped on it and my GUI improved drastically. Prior to the upgrade I was seeing some improvements by cleaning out history, old backups that weren't needed, and other crud.
We had the same problem until we upgraded to SMO 3.3. The GUI used to hang and was very slow using 3.2.
Someone had also mentioned that the location of the SMO server with respect to the repository could cause performance issues also. Currently our repository does not have SMO server installed. We just connect directly to the SMO server running on the target/source host. Not sure if this makes a difference or not.