Some people regret upgrading to Shopp 1.3 the moment they want to view their site after the upgrade.
The site is slow, in some cases sloooow, and in few it is really slooooooooooooooooooooow.
This is caused by not being able to write to an errorlog, which generates an error, which needs to be written to the errorlog, which… you get the picture.
Luckily one of the developers found an easy fix for it.
Add the command below to your wp-config.php file, not at the very end but somewhere in the middle.
Keep in mind this only applies to Shopp 1.3
define( 'SHOPP_TEMP_PATH', dirname( dirname(__FILE__) ) . '/shopp_temp/');