Hello Annabel,
To move entire projects export them as Aperture Libraries, and then import those Libraries into the other Aperture Library:
- Select the Project in the Inspector, then
File -> Export -> Project as Library
- In the other Library do:
File -> Import -> Library/ Project
But I am not quite convinced, that the size of your current Aperture Library is responsible for the slowness of Aperture - Aperture is designed to cope with huge libraries.
You may want to post your hardware setup and details of your library, and some of the hardware experts here may help you to find the reason for the slowness.
A huge library should only be a problem, if the projects are too big, and if you have many, many smart albums at the root level of your library.
So keep the projects small, and try to move some of your smart albums to lower levels in your folder structure (then Aperture does not need to scan all of your images to build the smart album).
Other reasons for Aperture's slowness may be, e.g.
- An overfull system drive and/or external drive (keep at least 20% of your drives empty)
- lack of RAM
- a corrupted Aperture Library, that needs repairing
Have you checked those options, before you split your library? It would be a pity to split it, for you would loose the ability to browse all parts at the same time, to use all your images in the Media Browser, etc.
Regards
Léonie