in the "launch settings" appears some soundcards, but I only want to play with general midi, and doesnt appear!1!1 (sorry for bad grammar) and, I already configure this with the "config midi" command (or something like that)/the mortal kombat (1992) game settings conf. File and coolsoft VirtualMidiSynth. But still, doesnt appear in the "card" settings

You can choose Roland + Sound Blaster in the Sound Setup, that should produce midi music with the sound blaster sound effects.

These settings should work for most DOSBox games:

Midi/Roland: Port: 330
Sound Blaster: I/O Port: 220, IRQ: 5, DMA Lo: 1, DMA Hi: 5

You can read more about the game options here.