I grabbed one of these RBwAPR-2nD&R11e-LTE-US off the shelf today at ISP Supplies  and wanted to see how hard it would be to make it work with Verizon Wireless.  I had an active SIM card from an old Verizon Jetpack to use with it.  I inserted the SIM card and fired it up and attached to the onboard 2 GHz WiFi.  As suspected, it did not work out of the box.  I did a little Googling and figure out Verizon uses an APN which is basically a way  LTE carriers differentiate themselves from other carriers on the same technologies.  I created the APN profile, applied it to the LTE interface, disabled the DHCP Client and I had internet.  This is simple and here are the steps:

1. Upgrade to the latest version of RouterOS.  This is covered a million other places. Reboot.
2.  Click Interfaces-LTE-LTE APNs and delete the APN's there. Make a new one named whatever you like.  Fill in the AOPN value to "vzwinternet".

3.Ok out of everything.  Double click the LTE interface and select your APN profile you just created.  

Count to ten and your device will connect to Verizon.  Modify as you wish.