When I updated the plugin, it reset all my store options

When I updated the plugin, it reset all my store options and broke my site. I've got some of it working again, but there are no options under the 'pricing' drop-downs and all prices are defaulted to zero. It won't recognize my custom template either, and I can't even figure out which template it's using. I've tried naming the custom template mp_product.php and single-product.php but neither work. It says it should be looking for these files under my theme folder, but they don't seem to be working:
Single Product Page
mp_product-PRODUCTNAME.php
mp_product-PRODUCTID.php
mp_product.php
single-PRODUCT_POST_TYPE.php (post type may be "product" or "mp_product" depending on your site's settings)
single.php
index.php