The first problem is likely to be due to your gallery's 'jbcore' folder being hosted on a different subdomain to the page containing your gallery's JavaScript embedding code. All gallery files should be on the same domain or subdomain as the JavaScript embedding code. Try hosting the 'jbcore' folder on your http://afrika.delosgaia.nl subdomain.
With regard to the second image being the first one displayed, the link you provided has a #2 at the end of it signifying that Juicebox should go directly to the second image.
When viewing your web page, I sometimes see only a slim AutoPlay Juicebox gallery.
Other times I load your page, I see a completely different Juicebox gallery with thumbnails.
Another time, both galleries were displayed with a map at the bottom of the page (same computer, same browser, same monitor).
Your web page is not being rendered consistently and, as I cannot always view the gallery in question, it is difficult to try to determine the problem.
However, I have not been able to replicate the problem using the configuration options from the XML file whose URL you posted above.
Try viewing your own gallery on a page of its own (by placing a 'jbcore' folder and a stock 'index.html' file inside your gallery folder and opening the 'index.html' file in a browser) to see if the first or second image is initially displayed.
Also, as you have set changeImageOnHover="TRUE", make sure that your cursor is not in the thumbnail area when the gallery loads (or the image corresponding to the thumbnail that the cursor is over will be displayed).