What's bothering me really? Seems a wee bit rude, but, the simple fact that I use other image tools that then pick up the jAlbum created files is what's bothering me really.
That was your interpretation and never my intention. So what software is picking up jAlbum generated cache files? Can this "Auto discovery" be prevented if you plant an empty ".nomedia" file within jAlbum's cache directory? If this resolves the problem, then I plan on generating such .nomedia files.
For more on the .nomedia file convention, see
https://fileinfo.com/extension/nomedia