Hello FATIN SYAKILA,
Sorry to hear that you ran into this snag. I'll be glad to look into this for you!
Firstly, you'll want to make sure that you are opening your Storyline 360 project file from a local directory. Working directly on a network drive has been known to cause issues, so we do not recommend doing this. You can also check to see if the directory where you're working from right now is being synced to another location by program in your computer such as OneDrive. Disabling these types of applications might help with the loading issue.
If you're not working from a network drive, try doing a repair of your Storyline 360 installation to see if this helps speed things up. If the issue persists, would you be willing to share a copy of your project file here or in private by opening a support case so we can take a closer look at what's happening? We'll delete it when we're done testing!
