What is false-positive?
The false-positive detection is when files or URLs that are incorrectly identified as malicious by the antivirus program. For wider explanation please refer to the article: https://support.avira.com/hc/en-us/articles/360002183358-What-is-a-false-positive-Avira-Antivirus-detection
Why one anti-virus detects potential threat in a file where other AV is not?
Each anti-virus software vendor is designing the AV software using different techniques and uses different methods to detect a threat. Some methods may not be able to analyze files protected with "packing" software that are used to protect against crack. For wider explanation please refer to article of one of AV software vendors: https://support.norton.com/sp/pl/pl/home/current/solutions/v118593681
Why some IGC software is detected with false-positive result?
IGC is using software known as "packers" to protect own software against reverse-engineering and crack. This approach is protecting both sides, us as software vendor against illegal software cracking, and customer, who is served with higher assurance that purchased software will not be cracked and published in public. IGC software does not contain any malware or code that can harm, control or collect personal information from customer's computer.