Cannot edit start up splash screen

after the 1.7.2 update texture packs cannot edit the boot up splash screen here is what i found testing http://youtu.be/YeEVarg5Rd8 <-- this may still be uploading [editing the spash screen works in 1.7.2 but to my testing breaks in 1.7.4 1.7.9 and 1.7.10]