Whoops, forgot a step:
Open "my computer" and hit "Map Network Drive" and find ur CD Burner on the network, that should make it MORE likely to be able to burn CDRs, not sure though. "Map Network Drive" justs makes a link between the drive and the computer accessing it so the cd burner will get a letter on the host's computer. About buffer under-run, make sure you have a burner with "smart-burn" or some other anti buffer under-run technology.
If it will not burn CDRs after that read this:
First you'll need a program to make Macros and access to a comp with VB6(I can do the vb part 4 u).
What will need to happen is when someone copies a file(s) onto a specific folder on the host comp., it will send a message through a vb6 program to another vb6 program on the host wich will start a macro thats fires up the burning software and burns the files. It'll take a lil bit of work and maybe a little cash but if you need this feature its the cheapest way to go.