first attempt

hi all ..i'm new to all of this and dunnow what i'm talking about so excuse me if i talk nonsense

i have an avifile with japanese subs and would like to add other subs to it(join them together to give the avi subbed to someone else

i got this far:
used BSplayer added the subfile(it rolls over the the japanese subs(i donot mind if the jap.subs cannot be removed if this can be done ...how??)

now the biggest problem when i want to save the file including the new subs and play it in wmp i still donot see the new subs

sure hope this can be done somehow and that i'm doing it wrong
thanx in advance for your help/advice