I have solved it already by checking in box apply and then unchecking box apply. but this bug is for everyone using this router and i just wanna mention it to you. and than it is up to you to fix it. and i as beta tester i did my job from my side and if i finding more bugs i will reporting to you. thanks for your time reading my posts.
On fresh install of new firmware, router as default responds to ping as you see in image XR500-0 it is unchecked but still responds to ping see image XR500-1-2.
finded a bug at least after all steps and reset to factory via reset botton and did a port scanner test on grc.com router as default gets pinged from internet even with ping to wan option is unchecked and i think need to fix.
Thanks, i missed DumaOS3.3 at the end of file name: XR500-V2.3.2.134-dumaos33-rc14 and thought it was the latest version in Netgear website download page, sorry my bad.