Yes you can use it. You can't break a mod with a texture or sound addon. The only one I would be wondering about is the XXI U-2511 for GWX 2.1 It has a DAT file so I don't know if OLC has modified any XXI dat files against the vanilla GWX 2.1 dat file?
If not then you just use JSGME to overide it.
If yes then I will have to remedy this...
