slow scroll

[blackholeearth]

this current krpyton outlookgrid is slow according to plain datagridview scroll, event with 100 item , 1000 item , 5000 item.

i tried this , orginal or influencer i dont know. https://www.codeproject.com/Articles/14388/OutlookGrid-grouping-and-arranging-items-in-Outloo

this one's scrolling speed is onpar with plain simple dgv.

is there a way to findout what has caused this speed slowdown, compared to original project.?? fix that or make those features optional.