1) Include your debug.err file in your report. The debug.err report includes system information which can be important, and can help give us clues as to what was going on when your problem occurred.
2) If it's a crash, please include a SmartException log if you have one. You can download SmartException at http://www.stardock.com/products/smartexception and there are also instructions there. Please run it while testing. The submit button in the SE dialog does not yet work, so you will have to open the log directory and open the file as a text file.
3) If you can reproduce it from a save game, send us the save game.
4) Screenshots are often helpful. To make a screenshot, hit Alt-PrtScn and then paste in a paint program and save as a jpg.
5) Please give as much detail as you can when describing the bug.
6) Please do not include unrelated suggestions in your bug report. These should be made in a separate post.
7) When e-mailing files for a bug report, please link to the post/reply here in the forums where you reported the bug. You can e-mail the files to firstname.lastname@example.org