In the WA_Globals.php file, make sure the $WAGLOBAL_Root_URL and $WAGLOBAL_remoteRoot are set correctly.
it sounds like the $WAGLOBAL_Root_URL is set to the root of you domain, but the power store files are stored in a sub folder.
if the PowerStore files are uploaded to:
powerstore/
then the $WAGLOBAL_Root_URL should be set as:
$WAGLOBAL_Root_URL = "http://www.mydomain.com/powerstore/";
and the $WAGLOBAL_remoteRoot should be set as:
$WAGLOBAL_remoteRoot = "/powerstore/";