oracle 10g OWB linux and windows 2 databases on linux owb client on win setup

overview
      install oracle 10g 10.2.0.1 on rh ent ed 4 for em64t
      install oracle owb 10.2.0.1 on rh ent ed 4 for em64t same box as above
      install oracle owb 10.2.0.1 on windows xp
      connect to a sqlServer database to suck out data
      
Problem
      I havent used oracle and linux/unix this millennium
      Verify my install steps or suggest better
      
boot linux and update the whole thing.
craete dir structure based on ofa /u01/app/products/oracle/database/10g/rdb_home
craete dir structure based on ofa /u01/app/products/oracle/owb/10g/owb_home
ok not the best names but i just want to figure things out and have a proof of concept

log in as oracle
export oraclehome = /u01/app/products/oracle/database/10g/rdb_home
set sid=""
set all other variables
install db software and create general database at same time named rdb
set sid = rdb
start database
select global name all is good

set sid = "" again
run dbca
create database named owb_repo
create sample schemas
if the sys password is not the same as above i get an error cant create tablespace
I dont think thats correct but maybe it is.  it does make sence but then again it doesnt
ok so i create the database's
set sid = owb_repo try to connect to sql plus and i get errors cant connect
--please help here i forget the format of the connect string to connect to a specific sid is it connect user@sid  or what?

so i hop over to windows and install owb
all is well i connect to both databases through EM fat client

back to linux
switch oracle home to /u01/app/products/oracle/owb/10g/owb_home
set sid = ""
install owb
all is good

back to windows
start owb/repo creation assistant
try to create repo on linux box sid = owb_repo
gets 75% complete and i get an error cant craete owb users

now thats where i stand
when all this is resolved i want to connect to a sqlServerdatabase and suck out data
no i dont want to use dts i already know how to do that :)
my question here is ---
      if i have owb fat client on windows and owb repo on linux
      do i need the linux odbc driver installed and set up on linux?  if so i understand i cant use the 64 bit linux and db.
      or can i just connect to the sql server via fat client on windows and suck data from sql server into oracle sid rdb
      
main q is when i use dbca does that create an instance which requires an new home? or just a schema in the existing instance. it appears to me that it is a seperate instance but i want to make sure.  

Can someone guide me on what environment vars to set before running dbca to create the 2nd database?  
and what environment vars to craete before running owb
and what to set to start each service on linux.

This seems fairly simple to me i just cant find the amswer anywhere and i am tired of looking and reading :)
So i will offer max points and if it requires more detail i will get that at the office around 9:00 EST  i can make it crash again :)
if this q needs splitting up i will do that as well, to give points to all who help

Thanks in advance