One thing I learned way back in the days of Furious Pickaxe was break up the tasks early, often and into many parts. Frequently, progress is made in a "I'll do a little now and someone will finish later" which made it very hard to keep track of for larger assignments.
By breaking it up, it is easier to get them complete much faster, thus preventing "sorry I was gone for 2 weeks" hangups in the progress.
Another issue we faced was when a newer member completely reworked the game loop. While he made some improvements (which relied heavily on his changes and were difficult to isolate on their own), it made it VERY difficult come time for the final build, as I was unaware of all of the flag variables used.
Key point here: as the manager, YOU compile the code. You are in charge of the structure, skeleton, subroutine names, etc. Ideally you should be able to quickly draft the skeleton, assign subroutines to members, and fill it out that way, instead of trying to have everyone work together (it doesn't work too well that way).
Other misc tidbits. I frequently found myself constantly asking for updated code, just to see progress. Perhaps requiring either a daily update or weekly update on progress. If you are 2 days late or so, you are assumed to have dropped the project and its assigned to someone else (more than a couple times someone was just afk for weeks and there was no way to figure out what was happening). This prevents lulls in progress from stopping all development when a really key integral part is in the air.
Communication is key in all of it. Make sure everyone knows where you are going, why and how it will work. Perhaps even if you just request a weekly update, post the next day or so one large Progress update to inform everyone where everything is, kinda a State of the Union address type thing (dunno what the equivalent of that is if you aren't in the states, its when the leader gets up and talks about where everything is at on all fronts and where its going)
Great Quote:
"Time...LINE??? Time isn't made out of lines...it is made out of circles. That is why clocks are round!" -Caboose