Restoring Files and Filesgroups

I have a database with with two filegroups - the primary and one other.
Each filegroup has its own data file. I want to restore the database to a
different database server but restore only the primary filegroup.
When I try to do this, I get the following error for each of the data files
associated with the filegroups that I did not restore - File 'data file name'
was only partially restored by a database or file restore. The entire file
must be successfully restored before applying the log.
Any ideas?
BACKUP DATABASE test1
FILEGROUP = 'Primary'
TO primfilegroup WITH INIT
BACKUP DATABASE test1
FILEGROUP = 'FG_RW'
TO rwfilegroup WITH INIT
BACKUP LOG test1
TO test1log WITH INIT
--BACKUP LOG test1
-- TO test1log WITH NOINIT
RESTORE DATABASE test2
FILEGROUP = 'Primary'
from primfilegroup WITH NORECOVERY,
MOVE 'test1_Data' TO 'i:\test2_Data.mdf',
MOVE 'test1_Log' TO 'i:\test2_Log.ldf'
GO
--RESTORE DATABASE test2
--FILEGROUP = 'FG_RW'
--from rwfilegroup WITH NORECOVERY,
-- MOVE 'test_RW' TO 'i:\test2_RW_Data.mdf',
-- MOVE 'test1_Log' TO 'i:\test2_Log.ldf'
--GO
--RESTORE LOG test2
-- FROM test1log
-- WITH FILE = 1, NORECOVERY
--go
RESTORE LOG test2
FROM test1log WITH RECOVERY,
MOVE 'test1_Log' TO 'i:\test2_Log.ldf'
GO
ERROR MESSAGE:
Msg 4320, Level 1, State 4320
File 'test_RW' was only partially restored by a database or file restore.
The entire file must be successfully restored before applying the log.
Server: Msg 3013, Level 16, State 1, Line 1
RESTORE LOG is terminating abnormally.Hello, spoons
You also need to use the PARTIAL clause in the RESTORE statement. See
"partial restore operation" in Books Online.
Razvan