Today I was looking for a model to hold SD cards, and I found this one:
https://models.makewithtech.com/models/MOD220718QZJA0
When I go to customize it, only the $fn variable shows up, but there are a lot more variables than that in the description. I had a look at the source code, and I don’t see a [Hidden] directive there.
When I download the code and load it in openscad, I can see all of the described parameters.
Thank you for reporting this. I will take a look.
I found the problem. The word module is in a comment and this breaks the parser because you cannot have parameters after any modules are defined.
I will fix this in a future version of the parser. For now I just took the word module out of the comment and that fixed it.
Thanks again for reporting it.
You could spell module with a zero 
Yep. I could tell people to do that or I could fix the code. I think I will fix the code. Just need to get to it.
I was joking
Keep up the awesome work!
I just made a number of UI improvements to the site and release version 1.01. Check out the improved customizer layout.
Unlike other customizer implementations from the past you can expect to see enhancements a couple of times a month. Feel free to recommend enhancments.
Looks good! It’s working on that SD card holder model fine.
I have two observations from this experience:
Model designers should be careful to use the [Hidden] directive to hide things the user is likely not going to want to modify.
On the customization page for a model on your web site, I think the parameters should be open by default, not closed. I think would be intuitively more obvious how to parameterize a model if they are open by default.
@CoreyPDX I just published version 1.02 of the application and the MODULE and () parser issues are now fixed — at least I think they are.
The next issue to resolve in the parser if the use of [[ (nested brackets). These are not currently handled correctly.
So here is a challange. Find some more models, either on the site or on Thingiverse where the parameters are not correctly displayed. 
All kidding side. I really value feedback from our users and want to thank you for your help.