Redirect Loop and Misc 404 Errors

Hey all,

I’m having quite an obnoxious problem with my theme lately. Essentially, any time we try to perform certain functions on our theme that utilize the option-tree functionality of Arcadia (our theme) we get a 404 error within the pop-ups that come up after initiating various functions. Here’s a video example of what happens: http://www.youtube.com/watch?v=RQSnwT7eT7Y

After the 404 error, navigating to any wp-admin page is impossible, and each browser I use claims that redirect loop is happening. This all happened after we moved from Bluehost over to WebHostingHub. No plug-ins are causing the issue. Does anyone have any idea what to do?

[No bumping – especially after just 1 hour. If it’s that urgent, consider hiring someone.]