I have never had this problem with ASM. Just downloaded and that was it no problem with getting the products to display at all.
I am still on my ASM scripts which I modified a while ago and see no reason to change: http://www.oneautoshop.com/ . It sure looks dated though.
associate-o-matic rocks, but it has problems with all versions 3.05 and up, at least when it comes to german umlauts like ä ü ö Maybe the problems only apply for certain locales, don't know. I really, really recommend building upon the simple_store.php samples cript from the amazon developer connection site. This is relatively simple and good for learning PHP and basics of amazon AWS. It's also good since MANY scripts on the net are outdated and use the old ECS API which will be obselete soon.
I use joomla http://joomla.org and APF bridge http://www.deanmarshall.co.uk/demo/apf_bridge/ example bra-guide.com (my site)
amazon can return good results. For instance amazon pays me $1,500+ each month and growing. Scripts work well but it comes down to niching. You will not rank for products if you simply install a script and pull hundreds of products. I find that by providing product reviews, along with content related to the niche products you can gain great serp results and provide the links to your internal stores from within your review etc.
A modified version of mrrat's, since you don't have to do much and it comes loaded to the hilt with the entire amazon system.