There have been a couple times where some of the pixels on my tiles have not shown up while on layers. For instance, I have a boulder tile with the top 32x8 pixels are over Link. The leftmost 8x8 pixels appear totally transparent, as if that part of the tile is just gone
I'll get a screenshot to explain
[edit] Here are the screenshots
This is what the boulder SHOULD look like:

This is what the boulder looks like in the editor and player

However, when I add a box in the 8x8 pixel box that gets cut off, all the pixels show

To get a better view, here's the boulder normally, and with the pixels cut off. The red pixels show the ones missing

My guess is there is something in the code that removes 8x8 portions of tiles depending on how many pixels are there. How that got there, or what feature might cause that, however, is beyond me