1. Via the Tools-->Options, Misc tab accessible from the Control Center window you can set a default account. You can optionally leave the account parameters empty in any of the   eSignal NinjaTrader functions and NinjaTrader will use the default account set here.

2. To ensure you do not place duplicate orders in the event that a eSignal chart reloads you can check for the condition "isLastBarOnChart()"

3. You can check NTMarketPosition for a flat position before placing an order

4. You can create an orderId using the current bar time stamp + instrument name. Before placing an order, call NTOrderStatus and see if you get a valid return value. If yes, then the the signal has already been processed.