Trouble disabling "Next Button" until all objects are visited

I've had a good deal of experience in the past successfully preventing learners from progressing forward to the next slide until all objects on the current slide are visited. However, I'm building a new learning module and am having difficulty understanding why triggers and states are not seeming to register the way they have in the past (in previous files).

Along with one from the previous file (DLBCL_TestSlides) that may provide some insight/hints I can't readily identify that may help solve my issue, I've provided a file (MM_TestSlides) containing two examples of slides from this new project:

• Slide 1: I can't seem to successfully disable "Next Button" as I've been able to in the past, even though I've programmed all triggers and states the exact same way. I've tried multiple combinations of things, from changing the state-changes (eg, "when the state of none of [xyz] is visited, change state of Next Button to disabled" vs. "when the state of [xyz] is visited, change state of Next Button to normal" and so on) and the various objects and variable values that may or may not influence such a state-change. I can't seem to find ANY combination that would make it work, but it also shouldn't be nearly as difficult/complicated/tedious to accomplish.
• Slide 2: This is the only slide in my 42-slide file (17 of which require users to click/visit on-slide objects) that seems to successfully disable the Next Button before users interact with all the content. Is it because I went in and ensured every single individual object contains a trigger that influences/limits the Next Button? It's built similarly to its counterpart from the DLBCL_TestSlides file.

Note: I'm not entirely sure I fully understand variables versus state-changes and triggers, but even so, when objects are built to change the file-wide "AllObjectsComplete" variable default from false to true when they're visited doesn't seem to do anything at all. I'm at a loss.

I'd appreciate any help, thoughts, and overall input/suggestions in moving forward and building future slides like these. Thanks!