I have had this issue before in the past I cant even remember exactly what I did to sort it, however when theres nothing showing and you can hear the music try press Alt + Enter to bring it into windowed mode see if that works, im sure I messed around with my resolution too.
Also have a look in your mir2.ini becuase iv also had the issue where after downloading it has remained blank and gave me the same problem. Copy and paste this into it:
[Basic Settings]
SwitchPoisonOrder=0
DropItemsShow=1
ShowRevBar=1
[Chat Settings]
SystemFColour=255
SystemBColour=56
ShoutFColour=0
ShoutBColour=151
HintFColour=219
HintBColour=255
GuildFColour=219
GuildBColour=255
GroupFColour=64
GroupBColour=255
[Options]
FullScreen=1
InterfaceType=1
ScreenMode=2
BitDepth=1
MP3Volume=0
SoundVolume=24
BGSound=0
Sound=0