Ugdhar

You missed that part!

Well, given the information I have, I would have to say there's something wrong with it if it's not working. Just for grins, if you change FLAT_TILES to ItemGroup.MISC does it add your items to the Miscellaneous tab? If that works, then your custom tab is broken.

You may have Java 8, but you're not using it to run Forge.

You should really post your entire codebase as a github repository, because not seeing everything makes it so much harder to see what's wrong. What is FLAT_TILES?

You don't want the MinecraftForge repository if you are making mods, that would be for devloping/contributing patches to forge itself. Go to files.minecraftforge.net and download the MDK for the version you want to make mods for (only 1.14+ are supported on the forums), and the forge Docs (link at the top of every page) should help you get started.

1.12.2 is no longer supported due to how old it is. Please update to a modern version to receive support. See the LTS link at the top of every page for more information.

1.8.9 is no longer supported due to how old it is. Please update to a modern version to receive support. See the LTS link at the top of every page for more information.

1.7.10 is no longer supported due to how old it is. Please update to a modern version to receive support. See the LTS link at the top of every page for more information.

Please show where you assign the item to the ItemGroup

Your code is super hard to read with all of those method calls chained together, but I don't see anything that sets the creative tab (called ItemGroup I believe in the current supported versions) anywhere.

1.12.2 is no longer supported on these forums due to age. Please update to a modern version to receive support. See the LTS link at the top of every forum page for more information on supported versions.

You need to set the registry name of your stuff before you register them.

Make sure you have run the gradle task genEclipseRuns for your new project as well, if you're just copying files over, I would guess it's possible that running the new project could still target the original one.

I believe you should be able to right-click on the project in your package/project manager, and select "Run As" to get the options to run using that project.

https://www.minecraftforge.net/forum/topic/79304-112114-and-lts-system/ It's literally at the top of the page for every page, and explains what versions will be supported now and moving forward.

The ExampleMod that comes with the MDK (1.15.1-30.0.41) adds a listener for the FMLClientSetupEvent in the constructor of the main mod class, for a method also a member of the main mod class. My question is, is this safe? Or should the FMLClientSetupEvent method be part of a client-only class? Just trying to figure out current best practices to avoid the whole reaching across logical sides thing. Thanks for your input!

I was under the impression that 1.13+ could use 8-10, however I've only used 8 myself, so I can't honestly say. Glad you got it working at least!

1.7.10 is no longer supported on these forums due to it being really really old. Please update to a modern version to receive support. More information can be found on the LTS link at the top of every page.

Did you check out the LTS link at the top of every page? It explains everything.

I believe if you edit your original post you can change the title to add [SOLVED] or something to it to indicate it's been solved.

1.12.2 is no longer supported due to age. Please update to a modern version to receive support. See the LTS link at the top of every page for more information.

1.8.9 is no longer support, because it is very very old. Please update to a modern version to receive support. See the LTS link at the top of every page for more information.

I don't know how to be more clear than the instructions I gave

I've experienced this with the latest 1.15.1 build while I was tinkering with making custom mobs, so I went back and used the latest forge without any mods, and compared it to vanilla. I ran vanilla, spawned some cows from eggs in creative mode, flew in the air, and watched them wander around for a few. Did the same with a fresh forge world ( 1.15.1 - 30.0.41 ), and the cows were noticably spinning circles here and there, without any real reason that I could discern, and I did not see that happen with the vanilla cows. Let me know if I can provide you logs or video of it happening, I'd be happy to help any way I can, even if it's to get a working as intended

1.12.2 is no longer supported on the forums. You will need to update to a current version to receive support. See the LTS link at the top of every page for more information.