I change the themel.html to the one you edited, but there was still no change------the custom block I created did not appear.

I edited theme.html myself... moved xoops_contents above xoops_blocks-------but still no change when I created a custom block.

So I went back to my previous (unedited) theme.html, and created this time a custom block which I positioned "block left"--------still there was no change, the custom block I made (despite that I gave a weight=20) did not appear.

Maybe the problem is with the theme itself.