Clean off all the dried up old grease and apply very little silicone grease (NOT silicon paste!) or lithium grease. If the problem is sticky old grease, it will probably work pretty OK with no lubrication at all as long as the tracks are clean - the arm carriage mostly just sits on the tracks on its own weight, it's not a tight fit.
Your problem might also be a stretched servo belt which can't deliver enough torque to move the arm in little increments (I suppose fast moves are OK?).
Regarding emailing people, it is usually better to just post on the forum. People come here on their free time and don't get paid for any personal service ya know - on the forum, the answers benefit all the readership.