Well with the images and things I found that either getting them from Photobucket is the best way to make sure they are in your sig.
If NOT, for images right click and get the properties for it. Then highlight and copy where it says location. Then hit the img button OR type

THEN it should show up when you preview ^^
ALSO for adding links...its like posting int he forums. Hit URL Button and type in the URL for your Guild THEN it will ask for Page name...Type What your Guilds name is and VIOLA It should work ^^