When I open slightly plays, avast! discovery virus.
Before but (2006.6.19) promotes in today I continuously am playing
this game, has not reported. Whether is reports mistakenly?
NOD32 says nothing. File extension is also pretty unusual as it’s not infectable so i can assume it’s false positive. Send the file to virus[at]avast[dot]com and wait.
If it is indeed a false positive, add it to the exclusions lists (Standard Shield, Customize, Advanced and Program Settings, Exclusions) and check scan it periodically using the ashQuick scan (right click scan), when it is no longer detected then remove it from the exclusions.
Also see (Mini Sticky) False Positives