it could be that your cd burner is not supported but if you have ever gotten it to burn a cd using that same software then it is supported and the problem must lie elsewhere.
also it could be poor programming of the cdroast software. i have never used cdroast for dos, it caught my attention because of xcdroast from linux, i guess somebody stole it from linux just like how windows is a knockoff of the original Xwindow system in linux.
the third thing could be that dos is too lame to run anything not because its console but because of its programmers. somehow they cant seem to make any software that does not have a serious bug that would allow a remote attacker to gain complete control over the system.
cdkiller [everything is to be replicate]