[Scribus] Importing pdf and ps files

[Axel Bojer]

I have a pdf-file that I have to use in my Scribus document, but:
Is it safe to import pdf-files to my scribus 1.3.3.3-document and then 
print it? I read something (but can't remember where) about difficulties 
concerning this, but they are perhaps already fixed in 1.3.3.3?
In the preferences for the preflight here also is a checkbox for
"Check for placed pdf-files".

There *is* a "File - Import - EPS/PS"-function, but not a pdf-function. 
Pdf2ps made my pdf to a ps-file so I could import it, but this took 
forever on my machine an never came further as 66%, so I just had to 
stop it the hard way.

I am also able to import pdf-files in a picture frame (seems curios to 
me, I would suppose it to be imported the same way as i eps/ps file), 
but this worked, and my resulting pdf-file made from my Scribus document 
seems ok (pdf 1.4).

But the preflight verifier gives me the mentioned warning about ?placed 
pdf?. I know I can turn this warning of, but why is it possible to get 
this warning in the first place? This makes me (the user) think 
something may be broken ...

What is the safest and best way to do to use my pdf-file in a scribus -file?

Best regards
Axel Bojer