Hi Tony.
You can absolutely import devices from HPOV NNM into the DCR (Device Credential Repository) of LMS. You can do it either by selecting the 'bulk import' button (under Common Services >Device Credentials > Device Management) to import devices from HP Openview, or you can do it through the dcrcli on the LMS server.
Also, there isn't a lot of overlap between NNM and Ciscoworks. Many customers use both in the same network as they complement each-other in capabilities.
Finally, for LMS issues, you might want to post on the Network Management forum under "Network Infrastructure" here in the left-hand column.
Thanks, and HTH,
-Joe