Hello,
I have such a problem, when I’m uploading my application(HTTP server and SPI communication) to the EMX module in Debug mode, it works perfectly fast. But when I’m trying to upload the program in Non-debug, it becomes VERY slow. What could it be? Does the size of the program (~250 Kb) matter?
Do you have Debug.Print statements in the code?
I have found that Debug.Print is very slow when there is not a debugger present, try remove them or have them conditionally execute only when in debug mode.
@ taylorza - Yes, I have some. Thank you for idea, I’ll try it 
I’ve also seen this especially when debugger is over usb… like if there’s a blocking process that check if tehre’s something to send over usb that interupts the normal execution of the application.