Fair enough. I mentioned these in another thread but it's crowded with other issues:
Explorer.exe will often hang, forcing me to kill start11, stop its service, then restart explorer.
Toggling left/center positioning is broken - Sometimes fails to slide icons to the left and all taskbar icons stop responding.
Icon dragging/rearrangement is broken - For example, in the "modern" layout, Dragging an icon between the icons at positions 2 and 3 will result in it being placed at position 4 instead of pushing icon #3 to the right. To clarify, I increased the number of columns in the settings. Maybe the rearrangement function doesn't properly handle that setting being modified.
Start11 menu does not reliably work when centered on taskbar (was an issue in .55 as well but .9 isn't working well enough to even test that properly. The native task bar keeps popping up instead of Start11 when centered. In .9, clicking the centered start button a second time would reveal the Start11 menu BEHIND the native one for a second before it immediately disappeared. Keeping the Start11 settings panel open somehow keeps it working more reliably.