Hi, Mon_raralio
You should contact the support of AVG I'll give you an opinion
In order to aggravate detection and reduce size of a file it might be packed with a runtime packer. Even though some packers are commercially available, many executables compressed with them are malware, or have a behaviour that presents a security or privacy risk.
Usually these packers employ encryption mechanisms and often manipulate the original executable code to hide the real functionality.
Legitimate software may employ some of these commercial packers. A packer detection does not necessarily mean that the detected file is malicious.
A PCK/MEW detected file is most likely not to be malicious if one or more of the following are true
The program is in use for a very long time and is known to the user
The program was installed by the user himself
The program comes from a trustworthy source
hugs