This block's name should be something like "Is there any running trade at the moment?". It just tries to find at least 1 trade, and if it finds one, it doesn't pass. Of course, it checks its magic number, symbol and type (buy/sell) if needed, these are the settings of the block. So you can have as many blocks from this one in one EA or multiple EAs. The block doesn't forbid the creation of trades. It's name looks like this only because it needs to be something short.
