With the Device Manager Test in LonMaker a Neuron 5000 chip has this high number of Lost Messages & Missed Messages (see below).
**********Beginning test run, 1 passes on 1 devices**********
[28/8/2015 18:06:47] TEST, Subsystem 1.RB-SerialIO 9, PASSED
The device passed all applicable tests.
Transmission Errors: 12
Transaction Timeouts: 0
Receive Transaction Full Errors: 0
Lost Messages: 4143
Missed Messages: 1751
Reset Cause: Power Up
Node State: Configured, Online
Version Number: 19
Error Log: No error.
Model Number: FT 5000
[28/8/2015 18:06:47] NODE OBJECT STATUS, Subsystem 1.RB-SerialIO 9, PASSED
Object Id: 0
In Override: 0
[28/8/2015 18:06:47] NODE OBJECT SELF TEST, Subsystem 1.RB-SerialIO 9, NOT SUPPORTED
The Lost Messages and Missed messaged result from the available number of application and network buffers being full. An incoming message passes from the MAC CPU to the network buffers. If the message get allocated a buffer the chances and it gets past the network CPU and has to be put into applicaiton buffers before it can be processed by the application CPU. Sometimes these error messages are associated with very high network traffic and a slow applications but often it is just the case that insufficient buffers have been allocated in the first place. Without specifying the number and type of buffers in the neuron C code the defaults allocated by the compiler should be sufficient assuming that your devices are sending and receiving network variable messages rather than application messages. Take a look at your buffer configuration and specifically the number and size.
Even if the number and size of buffers has been set in the neuron C code, buffer configurations are stored in the Read Only Data Structure that resides in the upper most part of the mandatory 2K of external EEPROM required for a neuron 5000 device. If an LNS tool only is used to load the application binary file into a fresh neuron 5000 device this will not set the buffers according to the code. Load the device using the -L and the -X options in the Nodeload utility to set the buffer configuration as well as the application