If you are running Oracle 11G DB with large amount of files in the project folder in a 64 bit OS, you'll find that the project will hang when you try to open it. Worked with IBM for several months and was not successful in a fix.
After spending a day of testing the scenarios, discovered that if the .rqs and .rql file reside in the same location as the data files it will read through the entire directory listing causing the slow response time it took to open the project. This did not occur in the 32 bit XP machine or Win 2003 machine. Went back to IBM support/development about findings and they confirmed that the .rqs when it resides on same level with the project files does read through the entire directory listing of the project folder causing the slow response. They think it's how Windows 7 handles reading network shares. There is no fix.
The workaround I discovered and confirmed with IBM is to put the .rqs and .rql file outside the project files. Hope this helps you all out there that have large project files, running 64 bit OS and Oracle 11G.