Hi Ian,
If you can't restore using the same technical name it means there are still some of the technical name in the BPC table that is stopping you with the restore.
delete environment using program UJ_ACTIVATE_CONTENT
run program UJT_CHECK_TABLE_ENTRIES
then check each table below and delete all the entries that using the old technical name.
UJA_APPL
UJA_APPLT
UJA_APPSET_INFO
UJA_APPSETT
UJA_DIM_APPL
UJA_DIM_ATHIER
UJA_DIM_ATTR
UJA_DIMENSION
UJA_DIMENSIONT
Andy