[RWP] Rendering tracks to a single track internally

[Alex Westphal]

Hello!

Lets say I have a huge project with a few different music genres in it, 
so I want pieces of classic, pop and rock bring to one song. To save my 
CPU for crashing or something like that, I want to make just one part of 
the song and then the other, just step by step. Now I know, that I can 
render the finished part to a wave file and reload it in reaper to mix 
it how it suits my needs, but is there an internal way to do this 
without rendering it to a external wave file first? something like 
internal bouncing or rendering? Or do I really have to make several 
small projects with the current instruments and the finished wave files?
-- 
Best regards

Alexander Westphal