Glad to hear a simple fix to the API Endpoint URL solved that issue! Thanks for calling out the updates to Shopify’s documentation around the value_type and string! values.
Rate limiting can be a balancing act. According to Shopify, their limit allows up to 2 requests per second for Standard plans and 4 requests per second for Shopify Plus plans.
In most cases, the best way to ensure you’re not being rate-limited is to set the Maximum requests per minute value in Parabola.
For your Filter rows (1) error, try using an Insert text column step first to create those columns. Just be sure to toggle Skip if column already exists. Check out this thread for more information on how to set that up.
From there, you’ll be able to target those columns and completely filter them out ensuring that no updates will be pushed to your metafield export.