Missing plug-ins after re-installing Pro Tools Le 8.0.5

[Erowe]

Hey all, hope you can help me here.

For the past few months i have been receiving this same message when using Pro Tools 8.0.5:

"A CPU overload error occurred. If this happens often, try increasing the "H/W Buffer Size" in the Playback Engine Dialog, or removing some plug-ins. (-6101)"

or

"CPU usage is holding off USB audio. Remove some plug-ins, delete some tracks, or increase the "H/W Buffer Size" in the Playback Engine Dialog (-6104)"

I have increased the playback settings to:

Playback Engine Settings:

H/W Buffer Size: 2048 Samples (Playback) 1024 Samples (Recording)
Host Processors: 2 Processors
CPU Usage Limit: 90%

DAE Playback Buffer
Size: Level 4
Cache Size: Large

Plug - In Steaming Buffer
Size: Level 8

But this hasn't made a difference. Today it got so bad that i decided to uninstall Pro Tools and Re- install it. Its seems to be okay now again but the new plug-ins that come with Pro tools 8 are missing from my computer. Plugins such as (eleven free, air reverb and maxim) I used the plug ins updater and the installer for pro tools 8.0.5 but they are still missing. I would really like to get them back as I have them on a good few songs.

Any help would be gratefully appreciated

Hardware Overview:

Model Name: MacBook
Model Identifier: MacBook2,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 4 MB
Memory: 4 GB
Bus Speed: 667 MHz