Customized Core Files Not Working in Child Theme

Dear All,

I have customization that takes the bid increment out, so that bidders may increase their biddings by as much as they wish to.

Today Mark has confirmed that I could use a child theme to prevent this customization from being lost with the next update.

So I have created a child theme using Theme Options — Design Setup — Create Child Theme. (I use Auction Press 5.4.)

Besides the style.css, screenshot.png, _footer.php, _header.php, functions.php, _homepage.php I have 3 core files (_functions.php, class_auction_defaultsphp and class_search.php) in the child theme.

The style.css works fine from the child theme (i.e. I am able to change the styling of the theme) but the customized core files do not override the ones in the parent theme.

What could be wrong?

Thanks,
Attila