^ I hear the trophy previewing thing... isn't so hot. Apparently only works with Kirby and that's about it.
As for previewing your textures... well... Maya's a tad wonky, so you may have to mess with it a little bit, but first:
"IMPORT" your .fbx file of the character. (You can open "Import..." under File, on the toolbar near the top of Maya.)
Once character is imported, you'll see their wireframe.
Open "Persp/Graph/Hypergraph". It's an option in a vertical toolbar on the left of the screen; the bottommost toolbar at the left side. (Has little pictures.) Right-click and HOLD, and you'll find "Persp/Graph/Hypergraph" alongside a bunch of other options.
*Make sure you are under the RENDERING tab. The tabs are at the top of the screen, below the toolbar containing File, Help, etc.
Once that's open, your character's wireframe should be a tad more condensed in its box.
To the right of the wireframe should be another box/window. Disregard the small text boxes in said window and look for "Rendering" -> "View textures" (at least, I THINK it was called Rendering >_> ).
"file1", "file2", etc. should pop up. Click "file1" (or whatever "fileX" is there.)
There should be yet another window on the right side... but you're nearly through. Said window should show a preview of the texture's skin.
*If you're under the RENDERING tab, you should see a bunch of small icons just below the tabs at the top of the screen. Look for the icon that has a paintbrush painting a blue ball with red.
Now click the window with your character's wireframe (the window is called "persp"), and then click the paintbrush-ball icon... Your character's texture should now be applied to the wireframe!
To edit said texture, simply head to where the texture's preview window is. You'll see a little folder icon. Click that, change the destination of where you have your character's .tga stored... and you'll preview from there.
~~If, for whatever reason, the texture previewing window doesn't open up AFTER you click "Rendering" -> "Show textures", I'd recommend either minimizing your window and maximizing it again (the program is quite weird), or simply restarting it (closing it out, opening it back up again).
Takes a bit of trial and error, and a bit of messing around, but you'll catch on.