Hi,
of course the SWPM assumes the ORACLE_HOME is /oracle/<SID>/121 as that is the value we use and we do not allow to deviate from it.
In addition, if it is a "new" installation, SWPM will not use an exisiting DB unless you specify it is MCOD.
and if you install it on a non SAP database, you will have a non supported installation, not sure if you want that