I got the exact same problem. I sent the author a screenshot and snoopdos.log but he never replied. That was about 9 months ago. I think maybe the author got busy or stopped development for some reason. The earlier version of Feelin (050517) doesn't have this problem.
The best programs for customizing Workbench are:
VisualPrefs - for nice buttons, gadgets, GUI layout
FullPalette (or LoadCMAP) - lock WB palette
Birdie - Window patterns
Newicons - icon palette mapping, remove stupid border
MagicMenu - nice menus
FF - replace ugly Topaz
Titleshadow - nice shadows in window titles
ModePro - set mode, palette, borderblank, fonts of other screens
...and if you're making your own icons, gadgets or backgrounds:
Iconian
PPaint
All are found in Aminet except FF which came on WB1.3 Workbench disk.
(Note: most of other above programs require at least WB 3.0)