What do you mean they stop because of the fire trails? Do you mean its something in the code? Cause as far as the movie goes, when Marty arrives at Doc's Mansion, its raining pretty hard, straight till the next morning. I dont think it'd make much sense to stop the storm right at 10:04, unless it has something to do with the code. Not to mention that it was that way in 0.2d.
And as far as the hoverboard in the Deloreans, I agree. Only the BTTF2, BTTF3 and BTTF3 w/ railroad wheels should have the hoverboard in them. That is, if this would even be possible.