I know it's a workaround but I cover the entire site in a calc grid then use the remove points within polygon tool to remove any calc points not on walkways. The end result is one summary that for all the walkways.
Russ, in the schedule manager dialog box (specifying a schedule) set up your schedule and order of fields. Next save (upper left corner save icon) and give this a name "Custom schedule with BUG rating" or whatever. Now when you specify a new schedule choose this name from the Schedule Name list where it normally says <New>. I've created several and it helps with consistency.
Yeah, you'd have to save yourself a schedule to have the ability to continually use a customised one.
As for the continuing calc line thing, until they re-instate it you can possibly workaround by disabling the calc summary for those lines, and then use a statistical area to cover those lines (if the lines are conflicting with other calculations you can put the line calcs on a different project and then tell the statistical area to only look at that project. The downside is that the statistical area summaries in the calculation summary schedule go down the bottom of the list, not in alphabetical order. They also won't show certain bits of data, such as Grid Z values and the like.
It's messy, but that's the best I can suggest until things change.
I agree that a method for being able to continue line calculations at different points would be handy. I didn't know it could do it in the past, but I second the idea to bring it back.
As for changing order, you can already do this. Select the line of the column you're interested in (the side of the table, where the black triangle resides), then hold down 'Alt' and mouse up or down.