Instance ID script for MT4/MT5 - script per MetaTrader 5

This script calculates and prints out the instance_id for MT4/MT5 installations.

The instance_id is used in the roaming folder names such as

C:/Users/{username}/AppData/Roaming/MetaQuotes/Terminal/{instance_id}/

Please, find more details here:

• - MT4: https://www.metatrader4.com/en/trading-platform/help/userguide/start_comm#data_folder
• - MT5: https://www.metatrader5.com/en/terminal/help/start_advanced/start#guest

The original idea comes from the user JC, posted on the forum. Main changes are:

• Built-in Unicode conversion using StringToShortArray (wide chars, 2 bytes); this should presumably support folder names with non-ASCII characters;
• Built-in MD5 hashing using CryptEncode (CRYPT_HASH_MD5); this removes dependency from custom MD5 implementation;

The script prints current MetaTrader instance installation folder and corresponding instance_id in the experts log.