I need to open he gate that leads to Oerba 300 AF so that I can get on with the soy. I have found he gate at the 49th floor but that spot of them map is inaccessible. How can I reach the gas? Thanks in advance.
Chances are you're either missing a Wild Artefact, or you haven't unlocked the other gate to Augusta tower yet.
There's a panel in the other half of Augusta Tower (300 AF) that fixes a floating platform...its the only means to get to that floor (and Floor 13 I think).
Redouble your steps (use the Time-gate map if you don't know which gate triggers what or where to go).
Also be sure to get every single Gate Seal you come across, because you never know when you'll have to rewind time to re-collect something (this is true for the Bestiary as well). --- If you have a question about Guilty Gear, ask me anything! http://gear-project.tumblr.com/