I have created a package in Suitecrm V7.8…3 and i installed it in same version it worked fine. But when i install it in Suitecrm V7.9.12, It is installed well and when i try to open the module it throws Warning: You do not have permission to access this module.
What other errors do you see?
Please check also php_errors.log (or whatever your web server log is called)
I am not sure you can install packages across versions, like that. It might be better to upgrade the system to 7.9.x before exporting (even if you do it just on a test system)