As far as I can see it is rather old thread, but probably someone is still interested in it. As an alternative I can recommend an automated way of migration with cart2cart. It will help to move all products, customers, order history, etc from your opencart 1.4.9.5 to 1.5.6 (or even 2.0). I've tried it a few weeks ago and it worked pretty well.
Hello zorflax,
We are glad to announce that Cart2Cart supports ProStores and you can easily perform ProStores to Shopify migration. For more details you visit our page
Best Regards, Cart2Cart Team
Honestly, we've done quite a few big imports like this and they are nearly awlays quite painful to do manually, we have however used these guys a few times and they've been brilliant every time http://www.shopping-cart-migration.com/provided-services
We've only used them for the cart2cart services but they do offer from csv / database services as on the above link
It's a little more expensive I think to do it via the file rather than the shop but they do still do it http://www.shopping-cart-migration.com/support-service-plans how many products are you looking at moving?
I did the research on this a few months ago for a company I was consulting for (they ended up not switching).
This is a service I found that does migrations:
http://www.shopping-cart-migration.com/shopping-cart-migration-options/1066-magento-to-shopify-migration
So from my understanding and doing some research for you. Here is what I have found. BigCommerce and WooCommerce use two different hashing algorithms for their password storage systems for user accounts. My recommendation would be to use Cart2Cart and then send a password recovery email forcing all accounts that were migrated to change their passwords. You should be able to migrate all account and order information but the passwords would have to be reset manually by all of the users. This would also allow you to flush all of the old unused accounts out of the database as anyone who does not login to change their password after a set time could be purged from the system.
Cart2Cart offers multiple packages for support as well as DIY options for those who are more tech savvy. They also offer a "demo" service so you can trial run it. Honestly this seems like the best option in my opinion .
Litextension does seem very promising but I believe your still going to run into the password issue since there is a difference in hashing algorithms for encryption. My information is found here. They say they have a tool to transfer customer passwords into WooCommerce but it would be interesting to see what ecommerce's they can actually transfer from into WooCommerce.
Do yourself and company a favor. Outsource that crap =-p
http://www.shopping-cart-migration.com/
If you manually setup the category structure, attributes then usually its as simple as exporting & importing your products.
If you arent upgrading or changing your Magento core you can just clone your current installation to a dev, install the theme and workout any bugs (depending on your install).
I have a lot experience designing/building stores on Ultimo if you ever need any help. Shoot me a msg.
Cart2Cart supports all OpenCart versions, and the latest 2.0 as well. So you can easily upgrade your 1.5.6.1 version automatically (more info here). Nonetheless, Cart2Cart migrates only entities and template will not be moved.
You can try Cart2Cart to upgrade your Magento EE 1.12 to 1.14 automatically. Time of migration depends on an amount of entities in your store and can be calculated approximately with the help of online estimator. You can find more detailed information here
Here is an infographic with alternatives to Magento Go - Bigcommerce, Shopify, Magento CE, PrestaShop and WooCommerce. Probably it will help to make a right choice - What is the best platform to migrate from Magento Go
As far as I know cart2cart has announced a possibility to migrate from magento go to magento community automatically. http://www.shopping-cart-migration.com/shopping-cart-migration-options/5202-magentogo-to-magento-migration
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