E-commerce module problems - subproducts and product list not working

I'm trying to set up a small store on a client site using the e-commerce module, and having serious problems.

First of all - subproducts! I created two variations for apparel products, style and size, and edited the one apparel produc the store has (T-shirts) to include those (I clicked "generate subproducts" with all options checked -- that should do it, right?), but I can't figure out how to get them to show up on the page! When I go to the T-shirt page, I see no menus for varations, or any other way of choosing them - nor do any show up when I click "add to cart", or even "check out". At no point in the process does it show a customer the subproducts. Am I missing something?

Also, the product list view is horribly broken. When I try to view any sort of product list, I get an error message saying:

warning: Missing argument 3 for theme_ecviews_product_list() in
/[path to my web directory]/modules/ecommerce/contrib/ecviews/ecviews.module on line 285.

I checked line 285 of that module, and its the first line defining the function theme_ecviews_product_list, so I did a search for any occurrences of the function throughout the ecommerce directory to see where it was being called and what arguments it was being given -- only to find out it apparently isn't being called from anywhere! There were 0 occurrences of the string "theme_ecviews_product_list", so I don't know how or from where it's being called, much less how to give it the third argument it apparently wants.

Below the error message, what it shows makes no sense: the three product nodes that currently exist, wedged into a table horizontally. The first one's squished into an column about 4" wide, and the other two into columns that are about 1" wide each. I'm guessing this is some weird glitch where it's not sure if it's trying to list the nodes one after another like it would on a news page or something, or list them in some kind of a column view with their prices etc., and it's trying to some kind of freakish hybrid of both by wedging the entire nodes into the columns. Anyway, it makes the product listing completely unusable.

Has anyone run into this before? More to the point, does anyone have any idea how to fix it?

I don't really need the product listing, in a sense -- there are few enough products on this site that I could just create a page with a thumbnail and brief blurb for each one and links to the product pages, but that wouldn't automatically update if they added a new product at some point, so it seems like a non-ideal solution. Plus, Drupal insists on putting a link to the broken product page in the breadcrumb trail, so a user might click on that instead of the page I made by accident. So I need to either fix it, or find a way to hide it.