need help with configuring the plugin

i am new to WP so do not bear with me.

have set up a wp-site and now i try out some wordpress-amazon-plugins.

see the site: http://www.literaturen.org/ten
which runs a BETA-BETA-Site.

i just installed AmazonSimple-Admin

after some clarifications on the server i finally was able to fill in the correct

AWS-Key-data like KEY and security-key and Affiliate ‘ID.

now i have still some troubles left in configuring

It is highly recommended to activate the cache!
http://literaturen.org/ten/wp-admin/options-general.php?page=amazonsimpleadmin/amazonsimpleadmin.php&task=cache
/home/vhost/WWW/literaturen.org/ten/wp-content/plugins/amazonsimpleadmin/cache is not writable

Available templates:

This is a list of template files, ASA found on your server:
book
collection_sidebar_default
collection_sidebar_fav_games
default
demo
dvd
mp3
sidebar_item

well – how to proceed =?
What should i do now – in order to get the thing up and running?

Loook forward to hear from you

greetings

https://ww.wp.xz.cn/plugins/amazonsimpleadmin/