The nuke wouldn't be in game. I would render it in a modeler, and then just bring the video of the nuke going off into a video editor to edit in the actual explosion.
To Dr. Distracto:
It's somewhat hard to understand your post. You would need to edit the textures in an image editor. These can be programs like MS Paint, the GIMP and Adobe Photoshop.
I use Blender to model, and it's pretty easy to learn once you have the hotkeys down.
For custom HUD's, just make it in an image editor and set the part of the image that's not the HUD to RGB 0,0,0 or just alpha texture it black, so it doesn't show up. After that, just tweak the coordinates in the languagebank\english\gamebank\mygame\setuplevel.fpi where it says:
:state=0:hudreset,hudx=5,hudy=5,hudimage=languagebank\english\gamecore\huds\lives.tga,hudmake=display
:state=0:hudreset,hudx=4,hudy=8,hudsizex=16,hudsizey=16,hudimage=gamecore\huds\numeric1.tga,hudtype=1,hudmake=numeric
:state=0:hudreset,hudx=15,hudy=5,hudimage=languagebank\english\gamecore\huds\health.tga,hudmake=display
:state=0:hudreset,hudx=14,hudy=8,hudsizex=16,hudsizey=16,hudimage=gamecore\huds\numeric1.tga,hudtype=2,hudmake=numeric
:state=0:hudreset,hudx=85,hudy=8,hudimage=gamecore\huds\ammo.tga,hudtype=3,hudmake=status
:state=0:hudreset,hudx=88,hudy=12,hudsizex=16,hudsizey=16,hudimage=gamecore\huds\numeric1.tga,hudtype=3,hudmake=numeric
Same thing with custom menus, except change their coordinates in the other files in that folder.
Thanks for the comments everyone! I have been horribly busy recently, and will be until around the end of May, so look forward to some new updates then!