Hi DougS,
You are right, it is "LM", which stands for Link Master device. On the other hand, you can also change the device type to Basic Device by choosing right-click menu item "Change Device Type" in NI-FBUS Configurator 3.1 version.
To answer your last question: Yes, National Instruments has been supporting this product all along; in fact, the latest version of NI-FBUS Configurator is 3.1, which supports off-line configuration and supports many new interfaces like PCI-FBUS, PCMCIA-FBUS S2 and HSE/H1 linking device.
Please feel free to contact us if you have any question on NI fieldbus products. You can just send e-mail to "fieldbus.support@ni.com", we'll be happy to help you out.
-- NI Fieldbus Support Team