Hi baby09,
If you are specifically customizing playback settings (e.g., putting everything on auto forward or having the same font color for all words), you may want to check out Little Reader's Override or Multiple Edit functions -- these two functions allow you to apply your preferred playback settings globally or for all your lessons.
For more details about the Override and Multiple Edit functions, please refer to this article:
http://support.brillkids.com/entries/20586937-how-to-change-playback-settings-for-all-little-reader-lessonsIf you are trying to customize each word by replacing images, videos, or recordings with your own files, I suggest that you work on your edits from Little Reader's Advanced Play/Edit > Categories screen. This way you can work on editing an entire set of related words (categories) at a time, and you'll see that the changes you make will automatically be applied to the words shown in your Course lessons.
As you may have noticed, each Word Flash, Multisensory, and Picture Flash session in your daily lessons shows certain words taken from 2-3 different categories, and for every day, one word from each category is "retired" and a new one is introduced. Since the course lessons are set up this way, you'll most likely find that it's a bit difficult to find which word/s you'll need to edit for the next day.
For details about editing words from the categories section, please have a look at these articles:
Editing Categories -
http://support.brillkids.com/entries/20428831-editing-categoriesEditing Words -
http://support.brillkids.com/entries/20428861-editing-wordsAs for which categories you should start working on, you may consider working on the categories that are shown in the lesson you're currently at -- if you are in Day 1 to 5, for example, you can start customizing the Action Words 1, Parts of the Body - Head, and Common Animals 1 categories. Categories from the LR curriculum are filed in corresponding "Semester 1" and "Semester 2" folders.
I hope this helps!