Resource Tag & Assets Tag - What has happened here in SD

We used the Asset Tag in SDP 6.0 to assign our unique Asset numbers, these appear to have been imported into SDP 7.0 as Resource Tag, however.
- Columns in view doesn't have this as a choice
- Reports in Custom Reports for Resources lists "Asset Tag" as a choice only but doesn't return the correct value, it gives the scanned "Resource Tag" only, not the entered value from Assets in SDP 6.0. There is no choice available for "Resource Tag"

We really need these two columns to be independant and accessible. The Asset tag being returned in reports is usually the serial number of the scanned workstation, all the ones we manually entered in SDP 6.0 can only be viewed one at a time by opening an Asset and looking at the "Resource Tag" field. At the moment I need to know our last Asset number and don't appear to have anyway of searching for it or reporting on it.