David,
I knew I once hit this same “trap” you’re hitting now.
Have it documented. See attached my TaskBrowserListCtrl class as an example for you to cross the bridge.
ForDavidWoods - derived ListCtrl class example.py (2.4 KB)
You’ll find the key in line 34 of the snippet:
idx = self.InsertItem(key, tsk[1:], -1) # -1 prevents image in column 1
Good luck!
Thom