Status of limitation only act to bar filing a lawsuit (it's also an affirmative defense). However, the statute of limitations does not act to hinder "testimony." In other words, if you file the law suit after the time limit, then the Defendant has a good reason to ask a court to dismiss the case. If the time has not expired, it's a good idea to file as soon as practicable assuming you have a cause of action.
You do not have to register it for it to be valid. However, it is a good idea to register it, so that if something happens to you, someone can actually find it. You register it with the Register of Wills. In Baltimore City it's located at the Circuit Court on Calvert Street.
You can sue the assailant for the damages that he caused. You should seek the help of a personal injury attorney. Most take these types of cases on contingency.
You could also file criminally against the assailant as well. The State would then take over the case and see whether there are grounds to prosecute.
It depends on further facts a circumstances. Where were the police? Inside or outside? Did you invite them in? Police are allowed to pat you down for weapons for their own security. Since the call was related to domestic violence, the police probably conducted a cursory search of your person to find weapons. There is a doctrine called the plain feel doctrine as well. If they stayed on the outside of your person, but felt what they reasonably thought was a "smoking device" then they have cause...
You may qualify for the assistance of the public defender. Contact the public defender's office in the county where you were charged. You need to apply 10 or more business days before your scheduled court date. Don't delay in applying. Good luck.
I suggest you sit down and show your business plan to an attorney. There are many factors to consider between a corporation and an LLC. They each have pros and cons. The issues include how to set one up, how to make an operating agreement, taxes, etc. It can get complicated depending on your goals.
The cost to file a lawsuit is $28 in the district court. Plus you'll have to pay for service of process which can be upwards of $60 or more, depending on the method you choose. You will also have to expend the time to properly prepare a complaint with exhibits, show up to a court date, and have a trial. This can take several hours of time. Depending on where the defendant lives, Maryland may not even be the proper forum to sue the friend - it may be in another state depending on your...
You can file for early expungement but you must show "good cause" to the court as to why the relief sought should be granted before the three year expiration. Once you file, the State will have an opportunity to object - but then a hearing may be granted. Whether you can demonstrate good cause based on early completion of probation requirements would be at the discretion of the judge.
You may ask the court for him to award attorneys fees and the court could grant them. But that award is typically made at a final trial or at a pendente lite hearing. Seek a consult for more information.