We just purchased a like new Dymo 450 and we were having the same issue. I discovered that you can download old versions of the Label Software. I downloaded DYMO Label Software 8.7.4 and it allowed me to create the template per the old instructions and will print the labels. I still I can't get a Bin Location on the label, still searching for a solution to that.
If you are using the DYMO Connect software, you can name the fields you add by clicking on the the three dots button "..." on the left-hand side navigation pane:
This will take you to the Label Properties page where you can rename the objects to be the same as the "Merge Fields shown in the Preferences -> DYMO page in Stocky:
If you have blank fields in stocky, like supplier_code for example, the label will print out whatever label you had for the item from your template. Which is why I had to make the label show blank on my template:
I hope this helps, God knows Shopify ain't helping.