Error message "Not Enough RAM" to run Panotool plugin

Hi ,
I run PS CS2 and Panotool plugin on my new winxp Laptop with 2Gb RAM. I
already upgrade from 1GB to 2Gb RAM but still get that error
message. "Cannot complete this command because no enough memory (RAM)"

Is there any PS workplace or stroage setting I need to
configure ?

I goto preference ->Memory and cache.
Default seting as below :

Available RAM : 1760Mb
Maximum use by Photoshop :55% (968Mb)

I h've tried reduce to 10% (176Mb) or increase to 90% (1584Mb), still error.

Anything I miss ? Pls help. Thanks.

Daley.