Hello Harold,
Unfortunately, we could not reproduce your issue. (We tried to create more than 1000 orders and all of them were successfully).
For further investigation, please provide us with the following:
1. The market order type you have created (TrueMarketOpen\MarketOpen\MarketOpenRange\OpenLimit).
2. OS version you use.
Please provide us with the requested information above and I will send you the instruction on how to build the log (messages between a client and a server).
Then, you will need to provide us with that log, so we can go forward with further analysis and investigation of your issue.
Thank you.