Yes, we use it all the time.  We have custom forms that we use for message traffic as well as the standard ICS, WX message forms.  We have integrated our FLmsg / FLamp files into a linked folder with ARIM/ARDOP.  Incoming / stored messages are shared between ARIM and FLmsg / FLamp.  This allows for sharing of traffic outside of the standard net times and acts as a backbone network between select stations.  Those shared NBEMS files can then be extracted from ARIM and seamlessly resent on another net using FLmsg / FLamp. 
N7WWA