Have you attempted to follow the instructions yet? It sounds to me like you downloaded SheepShaver and attempted to run it without configuring it first, as per
https://www.emaculation.com/doku.php/sh ... os_x_setup .
In big bold letters, the documentation states
Quote:
SheepShaver will not run without a compatible ROM file. If SheepShaver does not find a compatible ROM file, it will immediately quit on launch.
Since you've got a new world ROM file, you just need to follow the step that states
Quote:
When you have acquired a compatible ROM file, rename it “Mac OS ROM” (without the quotation marks and without a file name extension) if that is not yet its name. (SheepShaver will recognize a ROM file with that name in the same folder when no prefs file is yet configured.)