I am using jAlbum version 23.1 in combination with the skin BluPlusPlus 5.1.0 and the style “arcs”. For the thumbnails I use “frames”. In the settings of the skin I have selected “frame” for the thumbnail at 80%, but when I subsequently generate web pages those frames are not displayed. According to the helpdesk of jAlbum, they get the next errors in their console:
Error applying filter 'class BPPFrameHandler to image Stockholm.jpg:
I have replicated your problem in jAlbum 23.1.
Do you know which version of jAlbum introduced this error? The error does not occur in jAlbum 18.2.3, but I don't have any other intermediate versions of jAlbum installed.
It looks like 23 or 23.1 as I have 22.1 installed and that is OK.