The bug only happens when the counter is facing to the top of the screen any rotation turns the counter to show the hidden image side the moment it faces north again it shows the unhidden counter!
The units are set to allow any player to see them so no player side is impacting this. Vassal 3.7.20.
Here is the module: https://drive.google.com/file/d/14niOXkw_m4OcRtzXRapQ_of1PXxujiQf/view?usp=drive_link
I can’t begin to understand what’s happening vs what you want to be happening without a set of reproduction steps.
Taking a cursory look, you have your Mask trait set up to have “No image” for the View When Masked setting, which is almost certainly not what you want because it gives results like this:
From there, your Can Rotate trait is probably in an undesirable position in the trait stack because it’s giving you that big rectangle of background white space for any rotated piece in the mouseover zoom view. You also have “Autopeek on rollover” set for the Mask trait.
Reminder: with your current Mask settings (can be masked by: Any Player), you cannot truly experience how hiding (masking) pieces will work in truly opposed play unless you mask a piece, save the game, close it, change your module password, reopen the saved game, and take another player side.
