I have took another look at your blog. This time with my Firefox browser which has an active NoScript AddOn. By default all scripts getting blocked. But it is possible to allow single elements like the XSPF Flash player.
I have just noticed, that you are working on the code :) . no errors anymore on the Home page and the player is working.
Any advice on how to adjust this would be greatly appreciated.
This effect should be go a way when you clear the cache memory of your browser and you reload the page.
During your tests you have inserted the line of code with the URL of the gallerific library and the comment characters
/* */ into the footer. That is probably okay. But these kind of comment characters do not work for HTML tags like
<script>. You should remove them (BTW: they are visible at the bottom of your blog pages).
On the category pages and the pages with a single post one JS error still occurs.
Fehler: $("#thumbs ul.thumbs li").opacityrollover is not a function
If removing the comment characters does not help then you should place the line in the header of these pages. Maybe it is important that this library is loaded at an earlier point in time during the page load.
Since this error still exists on certain pages and the XSPF player is not longer visible on these pages, it is hard to say whether the player would work on these pages or not.
Is the WP-Member Invites plugin active again?
Does this certain error occur while the WP-Members plugin is deactivated?