I'm not sure, Minus. Maybe Harmon will chime in here. I'll see if I have time tomorrow to give the court clerk a call and see what I can find out.
What an arraignment entails varies somewhat from jurisdiction to jurisdiction, but usually it's just when a Defendant is first provided a copy of the charges against them and given a date to appear back in court with an attorney. In my county, prosecutors don't even go to the arraignments, and for those defendants who haven't made bond their arraignments are conducted via closed circuit TV from the jail.
Guilty pleas on felony charges at an initial arraignment are very rare and are not even allowed in many jurisdictions. (Traffic tickets and misdemeanors yes, but not felonies.) I assume the status conference is for MLS's attorney to meet with the prosecutor and see if they can reach an agreement on what the sentence would be if the defendant pleads guilty. We call those Preliminary Hearing Conferences where I practice, but there is no standardized name.
If no agreement between the prosecution and defense is reached, it will be scheduled for the next stage in the process. Where I am that would be a Preliminary Hearing, but since MLS was charged by grand jury indictment (as opposed to the DA filing an Information) he may not be entitled to a preliminary hearing. In Oklahoma you still get a preliminary hearing after an indictment, but in other states you don't. Just depends on what the statutes in Colorado are in that regard.
Procedures and practices vary from state to state and even county to county, but, regardless of procedure, ultimately the case will end in one of a few different ways: (1) An agreed guilty plea. The prosecution and defense agree on what the sentence will be. Could be probation, could be jail/prison time, could be a mixture of both, and will almost certainly include restitution. Most cases end this way. (2) A blind plea. The defendant pleads guilty without any agreement with the prosecution and the judge decides what the sentence will be. This happens when a defendant thinks (or hopes) he can get a lighter sentence from the judge than what the prosection is offering. Not as common as an agreed plea most places, but still fairly common. (3) A jury trial. You guys know what these are. In my jurisdiction probably somewhere between 1% to 2% of cases actually go to jury trial, and most of those are murders, rapes, child molestations, violent crimes, you get the idea. I'm one of the busiest prosecutors in our office. That's mostly because I prosecute sex crimes, child abuse, and murders. Why such a low percentage going to trial? To use my county for example - We file over 7,000 felonies a year. We have 6 district judges who handle felony trials. We have 26 jury trial weeks a year ... so if every single judge was doing a trial every single jury trial week (which doesn't happen) we could only do 156 jury trials a year (less actually because some trials last more than a week.). That's roughly 2% of the felonies filed a year. Actually, resources are only part of the reason more cases don't go to trial. Most cases really don't need to go to trial. Guilt isn't seriously contested. Defendant is willing to plead guilty. The parties are just wrangling over what a fair sentence is. (4) A bench trial. The judge decides guilt/innocence and punishment if found guilty instead of a jury. Very common for traffic offenses, divorce court, and small claims court, but pretty rare for felony cases. Most criminal defense lawyers know they have a better shot at convincing a jury that their guy is innocent than a judge. (5) Dismissal of the charges by the prosecution or the court. Usually happens when something goes wrong with the case (e.g., a witness changes their story, dies, can't be found, evidence is suppressed because of an unlawful search, etc). Not unheard of, but still pretty uncommon.
Clear as mud?