You can bring your catalogue and customers over with Shopify's own CSV files.
- Products: in Shopify, export products to CSV. In your store, open Products › Product and import the file. Options, prices, photos, tags and collections come with it.
- Customers: in Shopify, export customers. In Customers, use Import.
- Orders can be exported from MazaLabs in Shopify's format from Orders (Download, Shopify format) if you need them elsewhere.