The time it takes for the dialogue to disappear is tied to the contents of the package. For example, if you're installing a package that contains bundles, services or code that require some services and component to be restarted then the dialog will remain on the screen until all of such activities are completed. You can tail the error.log (crx-quickstart/logs/error.log) and monitor such activities in the logs.
If you are installing multiple packages with no interdependencies between them, you can simply refresh the page or just open another tab and go to the package manager to continue with the installation of those packages while the restart of bundles are services happen in the background. You can read more about this in the following older post:
Thanks for the info. I agree that the package content/size is relevant on how long the UI dialog would appear while installing the package. I am just puzzled because no matter how big or small the package i try to install, the behavior is the same.
In fact, if you may refer to below image what i have tried installing contains only one JSP file.
Referring to the other post you have linked, im not sure though how this relevant to the issue i am facing as the package that that i have tried installing does not contain any ACS common code/content.
I have raised this issue #152532 to Daycare and Im still waiting for some advice.
This is the proper route. If this shows up after you installed a service pack- then you need to check with support - which you have done. At this point - nothing more the community can do - we will close off this thread.