I did MVMCP solo in December, 2003 and thoroughly enjoyed myself--apart from nearly freezing to death! Keep in mind that I live in a warm climate, so while I was dressed in a cami, long sleeved shirt and blazer topped by a reversible fleece/water repellant jacket (equivalent of a pant coat), there were others wearing shorts and a fleece hoody!
It was very clear (no cloud cover) and very cold--even the CMs were bundled up and trying to stay warm.
Had absolutely no idea what I was doing when I went in. Picked up a schedule and sat for a bit at...can't remember the name, but it's in Tomorrowland and where they have the first performance. My plan was to focus on performances and fill in with rides, which worked well for the most part.
Attended MVMCP twice in 2004, first with a group from another board (the group split and rejoined several times based on interests) and the other night with one member of that board. While I enjoyed the large group, it's much more manageable solo or with one or two other people!
One thing we learned last year is that if you are not using a park ticket on the day of MVMCP, they may allow you to enter about 4:30 p.m. That isn't always the case, so you may have to wait a bit if you arrive then. They probably will let you in by 5 p.m. as the regular park guests begin to leave.
Get your event bracelet (have them fold back and secure the floppy end so it doesn't catch on everything), pick up several event schedules (need some for the scrapbook!) and head into Tomorrowland. We were able to ride the new Stitch attraction (not worth the wait, so it was a good time to do it), Buzz Lightyear (my first time--fun, but definitely lack hand & eye coordination!) and TTA before picking up dinner at Cosmic Ray's and heading into the theatre about 30 minutes before the first performance of the evening. While we ate dinner and waited for the first performance, we plotted our evening, which worked beautifully!
The weather for both nights in 2004 was absolutely gorgeous! The first night was a bit cool--a couple of people had to purchase sweatshirts--and the second night didn't get cool until around 11:00 p.m.