We need to understand here the true nature of your issue as this is nothing I can reproduce in Photopost
In showphoto as example you use the catmove box we pass to the adm-photo script the $catmove variable and the $pid variable and then this passes that to the function in pp-inc.php to move the image
move_image_cat( $pid, $catmove );
We then go to that function and use $pid to get the pictures cat variable and define it as $pcat
So something is missing here on your install and making the query fail and we need to find out what.
Code:
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