I wouldn't buy FD's stock to support them. They did their kickstarter for Elite years ago and are now a profitable company. Share prices does not affect profits, its the other way around. JWE2 release caused it, but that doesn't affect ED, at least not directly. A concern might be that FD might take resources away from ED to make JWE2 better in time for the release of the next film.
However, if i had spare cash to invest, i'd be sorely tempted to buy FD's stock because i'm pretty certain they will go back up in the coming weeks and months and this is just a typical knee jerk reaction by the stock market.