So I did play in the 1st round on Saturday morning. Unfortunately, I never made it back to any of the other rounds. I even carried around 18AL and my poker chips for most of the time I was at the WBC (which was only Sat-Tues) but it never got played.
I chose to play 1830 since it was about time I learned it and I was put at a table with a trio of very awesome and helpful gents. I gave them the up-front disclaimer that I'd never played 1830 or even much 18XX. They explained the differences between what I had played and 1830 and then helped me throughout the game. They left me plenty of leash to do my own thing, which I promptly choked on. To be honest (and it's really no excuse just inexperience), I made a mistake from the start that clearly cost me dearly. We played with the AH version and I purchased the NYC in the first SR because the "NY" on the NNH start space totally fooled me. When I saw where I was REALLY starting with the NYC it was clear I had screwed up.
I struggled to do much of anything for quite a while but I didn't mind too much since I was learning (the hard way). It wasn't until later in the game that I really screwed myself, buying and holding stocks that I clearly had no business with. As I was going last in the next SR round, the owner of that railroad sold everything to his other company and promptly sold all of those stocks in the next SR, sticking me with a company with no trains and just $2. I needed to buy a train in the next OR and since the very next train was the first diesel, $2 and all my money wasn't enough and I went bankrupt. Since there were already 5 stocks of both of my main companies in the bank pool I couldn't sell off enough stock to pay for that diesel.
Despite going bankrupt, I did have the distinction of finishing third in a four player game because of those stocks, they were the 2nd and 3rd most valuable stocks.
I have attended the WBC every year (except 2016) since 2003 and this is the first time I showed up for the first weekend. I think its now a mainstay for me and I'm excited for next year. I should have quite a bit more experience with 18XX by then.