Hello, please ensure that the latest update that you performed did not entirely remove flash. Otherwise, you might want to try the fixes stated below, and see if these can help you, or give you a guide to search for.

https://forum-narutoen.oasgames.com/page/show-post-47667-1.html

If no loading screen shows up, typically this is caused by flash not operating properly on this particular website, is there any way for you to check if flash is allowed for the game's website?

A Mac compatible miniclient has already been requested, but we are not aware of the current plan regarding the future of the game, just that there IS a plan. Only time will tell if there will be a Mac-compatible miniclient.