In all seriousness, are you using the high speed engrave? Reduce the speed to around 1000-1500 if so and see if it helps. A PNG file will not have the issue of open paths, although that looks like a vector image.
(completely irrelevant post follows. I missed the gaping holes in the engrave!!)
It’s an unfortunate artifact of the engrave process when using the “vary power” option, there’s nothing wrong the file or settings. It also shows up most on acrylic. Take a look at the deep engraved sections in the close-up of this little piece I made last night. There’s simply no way to avoid them, it’s a result of how the files are converted for printing.
You can, however, correct them post-engrave with a flame from a small torch, but that takes practice and would damage the surrounding un-engraved area in your design.
You can also run another pass at a different focus level to “soften” the engrave, but that also takes a lot of experimentation and with the more recent “auto focus”, seems incredibly difficult to do with any consistency.
Take a second look at the OP’s photo. It’s not the usual small bit of banding through an engrave. It’s a 10" tall design and entire chunks of it are missing.
Hummmm. In that case I would check the file very carefully to make sure you don’t have overlapping vectors hidden underneath the raster image. Sometimes when you use Inkscape to convert a file to a bitmap, the originals remain underneath the copy, and that will confuse the Glowforge software and make parts get dropped.
I use vary power about 95% of the time and have never had entire chunks missing from the engraving. I don’t think this is the normal LPI lines you can see with focused engraving on acrylic.
Thank you so much for your patience as we reviewed the trouble you were running into.
Unfortunately, it looks like your unit is experiencing an issue that we can’t resolve remotely. I want you to have a reliable unit, so I’m recommending we replace this one. I’ll be in touch via email to sort out the details. I’m so sorry about the bad news.