MetaQuotes has released a hot-fix update to its MetaTrader 4 platform yesterday - Build 1220. It focuses on the Build 1210/1212 issues that have been reported by some users: Fixed platform's slowdown that could happen when an EA or an indicator was performing many operations with chart objects. Fixed passing of non-constant string parameters to functions imported from DLLs. Fixed some other (unspecified) errors. The official update announcement is available in this MetaQuotes forum thread. If you find some bug or if you discover what the latest MT4 build actually changes in how the platform operates, please post below.