I'm sorry to hear about the alignment issues that you're experiencing. Unfortunately, there currently isn't a way to manually adjust the vertical or horizontal spacing between the labels within the Maestro Label Designer software. I have forwarded this suggestion on to the software development team in hopes that this type of functionality can be implemented in the future.
I pulled some sheets of the OL3012BK from our inventory to test against our PDF and Maestro Label Designer templates, just to ensure that the templates are accurate and printing correctly. I completed a series of print tests across a few different printer models and determined that the templates are set up correctly.
Your description of the issue sounds similar to what we'd expect to see if the page scaling options weren't set correctly, but you confirmed that page scaling is disabled in your print settings. In some cases, material shifting slightly as it's fed through the printer can cause minor alignment issues. Misalignment caused by material shifting would likely go unnoticed with larger labels, but can appear to be somewhat significant on smaller, round labels. If you're using the default or plain paper type setting within your printer options, you may want to try adjusting to a heavier paper type setting such as glossy, photo, labels or cardstock. This will typically feed the material through the printer more slowly, which has a tendency to reduce the slight shifting that can occur with desktop printers. Label paper is considerably thicker than standard copy paper, so making this adjustment has had positive results in reducing material shift and resolving alignment issues for users in the past.
If making this adjustment does not resolve your alignment issues please contact our support team for assistance. They'll be able to investigate the material you received to ensure that it was manufactured properly, and potentially send you samples from a different production lot to see if that improves your results. You can contact our support team directly by dialing 1-888-575-2235, or by submitting a support ticket at the link below:https://secure.onlinelabels.com/support/SupportRequest.aspx
I hope this helps. Please just let me know if I can provide you with any additional information.