Xcreds Package - preinstall and postinstall errors

[glitch]

I am experiencing installation errors when installing my Xcreds package with the following pre & post install scripts. The app installation does actually succeed, but the installer still throws the "Installer encountered an error that caused the installation to fail. Contact the software manufacturer for assistance." error. Any idea why these scripts would fail when added to the package?

The preinstall script just terminates any running instances of XCreds and removes any existing installation of XCreds.app from the /Applications directory, and the postinstall script creates a backup of the system.login.console authorization right, installs a login plugin for Xcreds, and runs a login script for the application.

#!/bin/sh

killall XCreds

if [ -d "/Applications/XCreds.app" ] ; then 
    rm -rf "/Applications/XCreds.app" 
fi

#!/bin/bash

set -e
set -x


script_path="${0}"
echo "script_path: ${script_path}"
package_path="${1}"
echo "package_path: ${package_path}"
target_path="${2}"
echo "target_path: {target_path}"
target_volume="${3}"
echo "target_volume: {target_volume}"
xcreds_login_script="${target_path}"/Applications/XCreds.app/Contents/Resources/xcreds_login.sh
plugin_path="${target_path}"/Applications/XCreds.app/Contents/Resources/XCredsLoginPlugin.bundle
auth_backup_folder="${target_path}"/Users/jadah.stone/Library/Application\ Support/xcreds
rights_backup_path="${auth_backup_folder}"/rights.bak


if [ ! -e  "${auth_backup_folder}" ]; then
	mkdir -p "${auth_backup_folder}"
    echo "Creating auth_backup_folder"
fi

if [ ! -e "${rights_backup_path}" ]; then 
	security authorizationdb read system.login.console > "${rights_backup_path}"
    echo "Backing up system.login.console"

fi

if [ -e  "${plugin_path}" ]; then
	
	if [ -e "${target_volume}"/Library/Security/SecurityAgentPlugins/XCredsLoginPlugin.bundle ]; then
		rm -rf "${target_volume}"/Library/Security/SecurityAgentPlugins/XCredsLoginPlugin.bundle
        echo "Removing existing Xcreds Login Plugin"
	fi
	cp -R "${plugin_path}" "${target_volume}"/Library/Security/SecurityAgentPlugins/
    echo "Copying the Xcreds Login Plugin to {target_volume}"/Library/Security/SecurityAgentPlugins/"
	chown -R root:wheel "${target_volume}"/Library/Security/SecurityAgentPlugins/XCredsLoginPlugin.bundle
    echo "Setting permissions to root:wheel"
fi

if [ -e ${xcreds_login_script} ]; then
    echo "Running Xcreds Login Script"
	"${xcreds_login_script}" -i 

else
	echo "could not find xcreds_login_script tool"
	exit -1
fi
exit 0