1. Here's why
MP4 files from Lumion with a resolution of 2560x1440 (Quad HD) or 3840x2160 pixels (Ultra HD) might freeze or look strange when you view them in Windows Media Player on some PCs.
This is a known limitation in Windows Media Player and depends on the PC specifications (harddrive speed and CPU speed). It is unrelated to Lumion.
1.1: Please view the MP4 file in Windows 10 Films & TV, MPC-HC, VLC or a different media player to resolve the problem. Alternatively, you can convert the MP4 file to a lower bitrate in 3rd party software and try to view it in Windows Media Player again.