Need help with PyQt5 Python script - will pay 0.19 XMR ($30 USD)

I wrote a 168-line Python script that visualizes web traffic using PyQt5. It primarily uses a QGraphicsScene to draw the visualization, and you can scroll to see the whole thing and zoom in using ctrl+scroll wheel.

I want to show a permanent "time line" at the bottom which just shows a labeled time axis, with notches noting the date and time of the current scroll position at intervals which make sense based on the zoom. I added another view which draws a time line and synchronizes in scale and scroll position with the main QGraphicsScene.

However, when scrolling it leaves random visual artifacts as if it's not redrawing properly, and also my implementation of the time notches is wrong.

If you can solve these problems (it's 121 lines of Qt) I am happy to pay 0.19 XMR/$30 USD for the trouble and probably more for future work. This is a side project and this thing has been blocking me.