How are your images #defined in resource.h? I seem to recall a difference between the original (and my) IPlug and WDL-OL. The original IPlug uses this:
Code:
#define MEH_PNG "img/Meh.png"
However, I think I have seen this in WDL-OL:
Code:
#define MEH_PNG "resources/img/Meh.png"
Also, mind your case on macOS (but I guess that alsol goes for WDL-Youlean).