I have been struggling with getting a USB760 to work reliably with a Mikrotik. I found this reference on a Linux forum, tried it and now the USB760 is stable, i.e. will not cause the serial port to drop and require a hard reboot.

By default, the modem comes from Verizon with a feature enable to have it also appear as a CD-ROM when attached to a USB port. Use Verizon Access Manager (VZAM) to disable this feature.After launching VZAM, wait for it to recognize and power up the modem. Once it has done that, the Preferences menu item under Options will be enabled. Select "WWAN Device" and disable the feature (see picture). You must wait for the modem to reconfigure before quitting VZAM and unplugging the modem.
It should now work nicely.

Cheers

jmlalley,
Thank you for sharing your experience.
In my case I can see the modem on Windows 7 only after I installed Broadband2Go from modem storage.
After I can see it in the following mode and can't change settings related to the CD-ROM disk: