Events Logs bigger than size defined

Hi all, I have a Biztalk server where I could see the application log is bigger than the maximum log size defined. Would it be possible that this is happening because of the "Overwrite events as needed" or I need to click on clear log ?

 

I also check on the group policy and it's also defined in the policy the maximum log size is 81920kb.

 

Application Event Viewer: Size: 556.0 MB (583, 925, 760 bytes) Max log size: 81920 KB When maximum log size is reached: Overwrite events as needed

 

Just one more question on creating custom event viewer as this Biztalk server could record up to 20 logs every seconds. I try to create a custom event viewer log but somehow it's not capturing any events. Does Biztalk have some special configuration for custom events viewer ?