A simplified version of this content can be viewed on my public website at
Click the "coins for sale" link in the left frame.
When this content is relocated to where I composed and tested it on my Windows XP/7/10 (I tried all of these) hard drive and is parsed using Opera, the "Show It" button fails. You should be able to double click "Denominated Coins->reverses", then select "Denominated California gold coins reverses", then click "Show it" and get a listing of coins with descriptions in the lower right frame. It works OK from the public website address and it works OK from my hard drive with any other browser.
Is there some way to fix this behavior? Long ago I reported this as a bug to Opera developers, but I did not receive a response and the behavior has never changed.