Curious to know if you have made any other types of cheese and if you had the same results?

Well….I have some thoughts that could possibly cause the melting issue:

-Raising temperature from 90 – 100 degrees too quickly could cause the problem.  If the temp rises too quickly, the curds can form a "skin" which can cause retention of whey during the draining and pressing.  That can cause the cheese to have a different texture/profile and cause the melting issue.

-Temperature of curds at step 9 ("Keep the curds at 100 degrees for 1 hour…").  If it gets too high could also contribute to the melting issue.  Sometimes when your pot is sitting in the water bath to keep the curds at temperature, the outer edge where the curds are resting on the pot itself can get hotter than the curds that are more internal in the pot.  Same issue as above with curds sealing and retaining whey.  Part of the purpose of the frequent stirring (with your hand at this stage) is to keep the heat distributed as evenly as possible (as well as to keep the curds from matting together).  Be sure the water in your outer pot is not too hot.

So…that would be my best guess as to the cause of your melting issue.

Have you tried a queso fresco or caerphilly recipe?  The queso fresco allows you to work with the curds and processes but doesn't require aging so you can practice the processes without having to wait so long to test your product.  It's much more "bland" in flavor but if you let it do a "mini-aging" in your regular fridge and don't cut it for a week or so it gets a bit more flavor.

The caerphilly is aged but only for 3-4 weeks before you can use it and can be another good opportunity to see how your cheese is doing in a shorter period of time.