@Simon Weinberger, yes thats exactly is the case , when i add and delete some component in the model while enscape is running ,it starts showing abnormality, and doesnot go away even if i undo the thing.
its a bit large file and uploading it would be tough, but will try for sure
but one thing i found out that the problem is usually seen with the large file say more than 100mb, small size file size doesnot have problem. i am not sure but it might give a hint about the issue.
The file i am dealing with is fairly detailed for me to get a walkthrough video, so after optimising with the help of purging and cleanup3 plugin too didnot help to reduce much. it is still around 120 mb.
my system specs are:
core i3 2120
gtx 750ti oc
12gb memory RAM
lastly could you please direct me a link to the exact location of the support section to submit my querries