Premiere cs5-trouble playing back in timeline. please help! (mac)

Question

im working on a 20min video in cs5. ive opened it several times to work on it and its fine. the past few times ive opened the project it is extrememly laggy and now wont even hardly play in the timeline. half the time when i press play it wont play, where the timeslider is it takes like 30sec to show the clip its sitting on. i should mention half the clips have been worked on in after effects via dynamic link.
specs:
macbook pro
2.3ghz intel core i7
16gb RAM
nvidia geforce GT 650m
i know when im working on school computers (windows) they tell you to set the scratch disks to different drives (c/d/e/ etc.)
how can i do this on a mac? is there anything i can do to speed it up or make it work since i dont want to move everything to my external and relink files (to work on a different computer)?
i tried doing a render, but it was taking forever so i cancelled it. at the rate it was going it would take 3 days to render (not export) ughhh. if thats the case, how long do you think it would take me to export it?
should i just not even bother to use premiere on my laptop?
my main concern is what can i do now about my project to make it play, as this is for a job and i need it done ASAP.
would have been done hours ago if premiere would work.
**cleaned cache. rendered audio and effects but not whole work area if that makes sense. rendering the work area would have taken forever and thats why i cancelled it.
only effects i did in AE are just a series of color corrections and a mask.
its 1080p 30fps video.
audio plays back fine in timeline just not video

Answer 1

When you are rendering, are you up or down resing?  ...what do you mean?
I mean are you outputing the same file kind, size and frame rate? Do you have the "Maximum Depth" checked or "Use Maximum Quality" ticked?
i used to render out AE comps as h.264 in CS6 and put them in premiere but premiere wouldnt ever find the media and would give me a green screen so i stopped doing that. dyamic link is the only way i can get AE comps to show up in premiere though i havent tried it with CS5
Weird. I've outputed files before and imported them just like any other media files without a hitch. That is a different discussion in itself.
i dont see any preview settings in CS5
Look under the program monitor at the bottom right. Should be a drop down menu to adjust previews. Or upper right corner of progam monitor ther is a pull down menu.
Also, have you tried using Media Encoder to do the render?
Message was edited by: EditorPete