Hi,
This can be a combination of several different problems:
1. Your page uses JavaScript to create contents the converter did not wait long enough until your JavaScript is done. In this case you can either increase HtmlToPdf.Option.MinLoadWaitTime, or use manual trigger feature as described here:
http://www.essentialobjects.com/doc/pdf/htmltopdf/eo_js.aspx#manual_trigger2. Your page can have different content sizes and that would result in different scaling factors. To eliminate this problem, try to use a fixed size outer div to contain all the contents. The converter will be able to detect this div size and use it;
3. The converter uses an older version of the WebKit browser engine which itself has some bugs. We have a new build that uses a much newer browser engine which generally produces much better result, especially for complex chart. This new build is not released yet but will be soon, we can provide you internal test build for you to try it out if you are interested. However depending on when you purchased your previous license, you may need to renew your subscription or purchasing a new license in order to use the new version. The general rule is the first year upgrade is free, after the first the older your version, the more expensive the upgrade is. If you can provide your order number, we can find out the exact cost for you.
Thanks!