I just grabbed a couple of rolls from the same production lot that you received to make sure there were no obvious defects that would cause a printer to have difficulty detecting the label material. The punch holes appear to be placed correctly and I couldn't see any visible defects, so I loaded the labels into a couple different DYMO printer models that we have on hand for testing. The labels advanced correctly when using the manual feed button on the printer models so it does seem that the printers are able to detect the material.
I've only used DYMO's standard label printing software (DYMO Label v.8) and had no prior experience using the DYMO Connect software, so I downloaded it to see if there was anything software related that could potentially be causing the issue. I noticed the same issue you mentioned in your post - when clicking the "Change Label" button the program seemed totally unresponsive. After tinkering with the program a little bit more I discovered that the "Change Label" button is not actually meant to change to a different label layout, but rather save any adjustments you made to the design itself. The wording is extremely confusing and I'm sure many others have been confused by it just like we both were.
To actually change the label type you have to click the "New" button from the toolbar. At that point you'll notice a dropdown menu that lets you select different label configurations. When I was able to change to the correct label configuration the printer did feed the labels correctly from the software. I did notice that the alignment was off though, almost as if the DYMO Connect software does not account for the carrier strips bordering the actual label itself. When printing from DYMO's other software (DYMO Label v.8) the labels feed correctly and are properly aligned. I'm not sure if DYMO Label v.8 has all of the features you require for your application, but if you want to test the software you can find it at the link below:
https://www.dymo.com/en-...abel-software-v8-windowsAside from possible software related issues you also mentioned that pressing the feed button resulted in multiple labels being fed through at one time. When using this printer previously did you ever notice if the label rolls featured any kind of black marks on the backing of the labels? We have discovered over the years that DYMO printers sold in the US differ from the DYMO printers that are sold in other regions internationally. The international DYMO printers not only look for the punch holes, but also look for black marks on the backing of the labels too. We've run into a few instances where a customer purchased a DYMO printer online and received one of the international versions rather than the US version, and then experienced difficulties feeding our labels since they do not feature the black marks.
I hope this information helps you resolve your feeding issues. If you decide you need to return the label rolls for any reason we'll be happy to take them back and provide you with a refund. You can initiate a product return at the link below:
https://www.onlinelabels.com/return.htmIf there is anything else we can help with please just let us know.
