1. DirectX changes it's rounding on the fly, so two computers running the same calculations won't necessarily end up at the same answers. You can't rely on this
2. The random number generator is a fixed function of the language you use. If you use the same seed then the answers will come out the same every time. So yes, you can rely on a blitz series of random numbers to come out the same. Though as Kurix says, you need ot call them the same amount of times. If one PC is running the main loop faster than the other (like 75 Hz instead of 60 Hz due to different monitor refresh and a VWait) then things'll get out of sync.
You may want to consider running the game proper on a server, and farm out the results of calculations (unit and bullet positions etc) to client machines, rather than calculate on all machines and try to keep them synchronised.
2. The random number generator is a fixed function of the language you use. If you use the same seed then the answers will come out the same every time. So yes, you can rely on a blitz series of random numbers to come out the same. Though as Kurix says, you need ot call them the same amount of times. If one PC is running the main loop faster than the other (like 75 Hz instead of 60 Hz due to different monitor refresh and a VWait) then things'll get out of sync.
You may want to consider running the game proper on a server, and farm out the results of calculations (unit and bullet positions etc) to client machines, rather than calculate on all machines and try to keep them synchronised.