But keeping track of action involves a lot of things. A number of panelists had worked in historical, or alternate history, or secret history genres, which require a lot of detail. And a good number of authors go by the rule that you can't alter a known event's known time, which means fiddling in all the other details. (Not a question I can help much with. As I observed to a fellow panelist before the panel, on a different topic, my stories are like oysters, they need to grow their own shells.)
They also had more tricks than I did for actual fight and action scenes. One panelist used Lego figures to block out the moves and worked from there. Another would time how long it takes to get across a place and what you can really say in that time.
My own comments were about bigger picture things. The smaller one is how long to keep your character on his feet. I described one novel where the heroine was wandering about the city streets. In the novel, she did it without sleeping. In the first draft, I pried it open and put her to bed. In the second draft, I pried open another place and put her to bed for a second time. Wandering about a city is not a fixed length event, but playing it by ear, it seemed like that. Made her wanderings seem longer that way.
For longer ones, there's things where the truly useful things are calendars,even if you have no real events to slot in. It lets you keep track of what weather is plausible. And if you want to have fun, there's always pregnancy, occurring within the plot and not in the denouement. If significant events turn on stages in pregnancy, you really need to know your times.
Other, less structured events -- well, what you really need is for the times to be plausible. That actions could take place in parallel. Though sometimes you can fudge it. I pointed out The Empire Strikes Back: either Luke learned really, really, really quickly, or Leia and Han faced one of the longest changes in human history. (Much silliness ensued about time dilation at that point. Which would have been pretty if there were room for it in the Star Wars universe. But since there are no allusions to time dilation and it has no other effects, we can chalk it up to the ability of stuff to paper over plot holes with adventures.)
It's important to give clues to the passage of time. I held forth on this because it's something I've always had problems with, because my characters are seldom in a position to be thinking about how long it had been since the last scene. Seasonable weather and holidays can help, sometimes. So can slapping a header telling the date and time on scenes.
Some discussion of how to keep track of all your research. Some programs -- alas, I do not remember the names. Keeping note cards not only with facts, but books, pages, libraries found in, and their accession number.
One of the tangents we went off on was about casts of character. One audience member needed to know how to handle all the people the character met at a wedding, and all he met -- somewhere else. Whereupon both panel and audience converged on -- don't describe them in such detail. Don't give the names of people just because he was introduced. Then I went off on another tangent about the need to suggest enough characters to give them impression of a full world about the story. They're nothing but wallpaper, but they need to be (lightly) implied.
And someone said something that set me off on a tangent. I recounted a story about a novel where the hero told the heroine that she had to be ready at prime or some such hour. And he forgave her for appearing within moments after the bells had rung. As if she had any way to know what hour it was until they rang. As if the times were fixed, and not when the bell ringer thought that the sun looked right. Shakespeare mentioned minutes, which shows he came after the invention of mechanical clocks. For the middle ages, the monasteries were a time keeping aid, with their bells. Indeed, they helped drive the development of clocks. They got up for a midnight office, which means that the Romans' sundials had limited usefulness. It's one thing for you to have to drill down to the minute or even second for action. Your character may not think of it like that.