1. These two vertices aren't needed and should be merged.
2. Deleting that overlapping triangle you deleted also the vertex, which was just fine.
I took your previous file and polished it to go on.
1. As I don't like messy parts I colored the background of the eye area and did a final test by setting the "Opacity" = 100% and checked the pattern with preview
2. I selected the 16 - Main Color triangles and "Edit -> Select Same Color" all other triangles of the front. I deleted them.
3. "Remove isolated vertices"
Before you are going to export your pattern, some setting are required. Deactivate the Rectifier - you will do the process later in LPDE
* "File -> Export as DAT -> Project on XY Plane (-Z, Front)" - the same projection plane we used on the import.
I attach my polished export file.
w.
LEGO ergo sum