I see you are running a version of the IHO roms. I am running Backside. If you just want a blank lockscreen with WP running on it, this is the best that I could do. This is using the stock CM7 lockscreen with a setting that removes all widgets, could be an issue with you wanting your music player.
1.) CyanogenMod settings->Lockscreen->style options->Lockscreen style->lense (that disables all widgets, the time, battery, carrier)
2.) CyanogenMod settings->Lockscreen->Lockscreen gestures->Build Gestures (make it simple or complicated)
2b.) Change the sensitivity. I use 3, it is somewhat decent to keep people from accidentally unlocking, yet not to sensitive where you have to be exact all the time.
2c.) check off "Use lockscreen gestures" and if you want check off gesture trails to see what you are tracing. I leave it off so nobody sees my pattern.
3.) CyanogenMod settings->Lockscreen->Unlock options->Disable unlock slider. (now nothing is on the screen and you unlock with your gesture.
P.S. as far as the music thing goes, you can also set a different gesture to launch directly into the music app, it would be one extra motion but just as good as a widget. If you use launcher pro, you might even be able to use the activities shortcut directly to pause, play next, back. Depending on the available options of the app. And then make each a gesture for that. That gets a bit complicated of course.