You guys have got to read more carefully. The secure boot screen shows that Loki is working. Download mode should actually say Download Mode in a very small box in the middle of the screen.
Pull the battery and restart your phone. Does it go past the secure boot error LG screen? If so what screen is next after letting it sit? If you want to you can PM me and I can help you.
Sent from my LG-E980 using XDA Premium 4 mobile app
Future Phone: LG Google Nexus 5
Current Phones: Samsung Galaxy Note 3 AT&T[Rooted], LG Optimus G Pro AT&T[Liquid Smooth]
Past: LG Optimus G AT&T, LG Google Nexus 4, Samsung Galaxy S3 AT&T, Samsung GS2 AT&T, Sony Xperia ion AT&T, Samsung Infuse AT&T(First Android Phone), All iPhones before that.