I tried it on my Laptop (DELL Latitude D820)

Core Duo T2400 CPU @ 1.83 GHz, 667MHz front side bus, 2MB L2 cache
15.4" WSXGA+ display running at 1680x1050
2048 MB DDR2-667 RAM (2x1024MB DIMMS)
NVIDIA Quadro NVS 120 graphics solution with 512MB TurboCache
120GB hard disk @ 7200RPM

WindowsXP Professional SP2

No problem here. I can use the editor as intended, no black lines.

But I also suggest that you think about separating the graphics from your exe That makes no sense!