As a CorpComm Official, you are a representative of the Corporation sent to this NARV to complete an assortment of tasks assigned to you by CorpComm.
In most cases, you will be but a low-level bureaucrat from CorpComm sent to preform an inspection, investigation, or some other managerial task. You will probably be spawned with just the essentials:
Right away you have a headset linked to the Command channel, so be sure to announce your presence as soon as you get on station and set up a meeting with the Captain to discuss whatever important task was assigned to you by your superiors. For the most part, your position puts you in a unique position in the ship's social hierarchy, and most of the locals will bow to your every whim and possibly even grant you all-access to keep you happy.
The bad news is you're also going to be a very juicy target for just about everyone who is considered to be an enemy of the Corporation due to your status. They'd be hard pressed to resist making an example out of you. It'd be a good idea to make sure you're always accompanied by at least one officer.
Just remember, though: You are not above Space Law and the Captain is still the station's ultimate authority so the use of force to impose your authority isn't recommended. Stick to your social advantage. If things go sour, CorpComm may recall you. If you feel your life is threatened, you may be able to leave the station the same way you boarded it. Just make sure you keep note of everything of importance, so you have something to report back to CorpComm.
On the off chance you are a ranking military or corporate official, such as an Admiral or an Executive, you command an immense amount of power. You'll likely board the ship with some fancy items to help signify and enforce your authority. You may also find yourself with increased, or even all-access to the various areas of the NARV, without deigning to ask for it.
While the Captain still maintains ultimate authority over the ship (including you while you are on board), your rank allows you to relieve him of Command and appoint someone else in his place. Like the Captain, you shouldn't have to do any manual labor yourself. Delegate to the Captain as he would delegate to his Heads of Staff.
Your relationship with CorpComm is a special one, meaning you will more likely get a response from any requests and transmissions to them. If you can, using the Communications Console on the Bridge or the Fax Machines in the Corporate Office is a good way to send an impromptu message. If you have completed your task and want to return to CorpComm, you can give them your formal report there, and negotiate with them to take action. The better written your report, the more likely it will be acted upon.
In the end, this is meant to be a roleplaying role, so try not to embarrass everyone.
CorpComm Officials cannot be antagonists (though harried crews might disagree.)