Here are the easy steps to opening a Java world in the Universal Minecraft Tool.
Did you know you don't have to own Minecraft Java edition to load a world in the UMT? It can load Java worlds you've downloaded from online or elsewhere.
Within each app in the UMT, there is the same starting screen.
Select Java to open the world selection window.
This will bring up a list of the Java worlds in your default Java saves directory.
Select the world from the list.
If your world isn't showing in the list, that means it's not in the default Java saves directory or you don't own Java edition.
You'll need to manually select the world files instead of picking from the list.
Click the Browse for a World... button.
Choose the folder that contains your world files.
Folder? Yep, Minecraft worlds on Java edition aren't one file, they're actually a collection of files all stored in a single folder. This parent folder is what you'll need to select. (It's the one that directly contains a file named level.dat).
If you play on Mac/Linux, you'll need to transfer the world files to the computer where the UMT is installed, then continue with the steps.
You'll know you've selected the right folder when the world name and icon appear at the bottom of the window.
Click Open World to open it in the Universal Minecraft Tool.
That's all there is to it. Have fun!
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