Forge: 1448
BLS: 1.3.8
Crash Report: http://pastebin.com/xxtizECE

Crashes as soon as it loads the better loading screen.

Try restarting minecraft, or give me a full log file please.

Full log: https://drive.google.com/open?id=0B090g8mHJkCWQjZudnJtOFp1MXM
Althought the latest version doesn't even show the better loading screen, it shows forge and then crash after 84% loaded.
Edit: okay this is weird, it shows the better loading screen when the jar is disabled (and doesn't crash), and it doesn't show it when BLS is enabled.
Log with BLS disabled: https://drive.google.com/open?id=0B090g8mHJkCWa1ZxLU5pX3NWSFE

Ok, that's strange. Can you try disabling the forge splash screen and trying again? (In your config directory there should be a forge loading screen related config file, change the enabled config setting to false)

(Better loading screen sort of try's to disable forges loading screen, however it fails the first time, causing a crash. The second time minecraft starts up, forges loading screen has disabled itself (because it crashed last time) and better loading screen can be shown).

That could explain what is happening if you didn't properly disable BLS or something went wrong. Although the log file doesn't have any mention of BLS in the disabled version (which you said it was working in).

I disabled it via curse's launcher wihich just put .disabled at the end of the file's name.
The first one is definitly using BLS, which gives an issue, and the second one says it ignores BLS because unknown format (.disabled).
It gives me the splash thread error no matter how many times I launch it.

Ok, that's not meant to happen then. Can you go to "C:\Program Files (x86)\Minecraft\Curse\Instances\Genesis\config" and open "splash.properties" and change the line "enabled=true" to "enabled=false"?

(And try again with BLS enabled)

I might have got the path slightly wrong though, I didn't copy-paste it.

It works after disabling splash screen.

Oh good. Next week I'll propably make it properly disable forges loading screen.

(Closing this as I think it's done, open a new one if you disagree)

This happened with mods. I had removed the cause; it still crashes. Additionally it was SkyFactory3. Logs: (to load it, use Microsoft Word and then download this: https://github.com/maxsize213/Crash-B =) ) Bye!

Can you try renaming "config/splash.properties" to "config/splash.properties.old"? (It looks like forge's own loading screen tries to find a resource that doesn't exist, rather than custom loading screen).

(Just FYI you should be able to open either files with notepad anyway)

Hang on, how did you find this issue? I haven't released any versions of custom loading screen or better loading screen for 1.10.2...