Nile is right in requesting a link to your live page because we cannot realistically know what your existing code is like, and that would influence how this question should be answered.
However, in an effort to save us all a bit of time, if your page has a valid URL DOCTYPE, the way to center anything within its parent element is to give it a style of margin: 0 auto;
So, for example, if your slide show is shown in this element:
HTML Code:
<div id="fadeshow1"></div>
You may:
HTML Code:
<div id="fadeshow1" style="margin: 0 auto;"></div>
or apply that style to that element via your stylesheet.
Back to Nile's wisdom, if you want more help:
Please post a link to the page on your site that contains the problematic code so we can check it out.
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