If anybody ever wants to find the correct prices for the different simple product combinations a configurable product can have in the frontend, ie for exports, this is one way to go

gistfile1.php

<?php

// The configurable product must be the one in question that we want to
// find the price for
$product = Mage::getModel('catalog/product')
        ->load(771);

// First, fetch the attribute combination representing the simple product
$attributes = $product->getTypeInstance(true)
        ->getConfigurableAttributes($product);

$childProducts = Mage::getModel('catalog/product_type_configurable')
        ->getUsedProducts(null, $product);

foreach ($childProducts as $simpleProduct) {
    $product->setExportPrice($product->getFinalPrice());

    foreach ($attributes as $attribute) {
        // We need to compare each attribute against every possible simple product
        // attribute combination
        $attributeCode = $attribute->getProductAttribute()
                ->getAttributeCode();

        $simpleValue = $simpleProduct->getData($attributeCode);

        foreach ($attribute['prices'] as $attributePrice) {
            if ($simpleValue === $attributePrice['value_index']) {
                if (empty($attributePrice['pricing_value'])) {
                    continue 2;
                }
                if (!empty($attributePrice['is_percent'])) {
                    $price = $product->getFinalPrice()*$attributePrice['pricing_value']/100;
                } else {
                    $price = $attributePrice['pricing_value'];
                }

                // Make sure catalog rules are applied to the additional price
                $product->setConfigurablePrice($price);
                Mage::dispatchEvent(
                    'catalog_product_type_configurable_price',
                    array('product' => $product)
                );

                $product->setExportPrice($product->getExportPrice()
                        + $product->getConfigurablePrice());

                // Move on to the next attribute
                continue 2;
            }
        }
    }
    
    // Do something with $product->getExportPrice()
}