I also applied for the Master's in Music Technology, but I didn't submit mine until February 1st. Did you ever get an email from them after you submitted, saying your application was complete? (I haven't heard anything at all, just the obligatory "thanks for submitting your app" when I submitted).
I DID try the netID thing, and had the same deal as you---able to activate, but "no roles define". So I don't think it means anything. I applied to GSAS as well so I'm incredibly confused.
Okay, so while writing this I got scared and this is what the website for Steinhardt says:
"PLEASE check the online system to confirm that you have successfully submitted your application. Due to the volume of applications and related materials received the Office of Graduate Admissions will only contact you if your application is deemed INCOMPLETE because of missing required materials. Otherwise you will hear from us when the Admissions Committee has made a decision."
I don't expect to hear anything from them until March at least.