Somewhat strange for Linux system, but easily addressable - using urls below I do see your entire server file structure instead of original Gallery 2 or Piwigo.
This is due to the fact that web server does not know to look for index.php

Easy to solve:
* create .htaccess in site's root and add "DirectoryIndex index.php" into it

With that addressed or by adding index.php to PWG url above I was able to see many photos.
Some thumbs did not generate properly from the first run
Could be ImageMagic issue, image content itself or some other issue.
This would be next step to look at

I don't see any issue with thumbnails!?

Hello Serge,

From your comments and from what I see, piwigo is not looking too good for me.

On occasion I can click on the blank thumbnails and get the full-sized picture, but response is very slow.
And many thumbnails are not loading. This should not be a problem because these are pretty standard JPEG pictures of about 1 MB size.

Finally, I was noticing that my disk space usage increased dramatically. I see the culprit - CORE files in the Piwigo root directory on my website. See attached graphic. I removed many of them, but they are increasing quickly. If I cannot get this resolved I'll have to remove Piwigo. It's too bad because the product in many respects looks excellent. I just need to get rid of the bugs,

Thanks,
Alan
P.S. I removed my Gallery2 files to clean up as well, so my disk space is about 2GB now (it was as high as 9)

amyalanc wrote:

Hello Serge,

From your comments and from what I see, piwigo is not looking too good for me.

On occasion I can click on the blank thumbnails and get the full-sized picture, but response is very slow.
And many thumbnails are not loading. This should not be a problem because these are pretty standard JPEG pictures of about 1 MB size.

Finally, I was noticing that my disk space usage increased dramatically. I see the culprit - CORE files in the Piwigo root directory on my website. See attached graphic. I removed many of them, but they are increasing quickly. If I cannot get this resolved I'll have to remove Piwigo. It's too bad because the product in many respects looks excellent. I just need to get rid of the bugs,

Thanks,
Alan
P.S. I removed my Gallery2 files to clean up as well, so my disk space is about 2GB now (it was as high as 9)

I have no idea what those CORE files are. Never seen them before
PWG similar to G2 does create derivatives but they should reside in _data folder
there is something else at play here.
You may need to take closer look at your hosting environment and its configuration as something may be misaligned there on system level