I have 128MB of memory, and as soon as I turn on the MPC only 118MB are left, so if you only have 32MB then I probably wouldn't expect to be able to load more than 20MB of data in the ram at any time (i.e. you're entire CF card will not fit in the memory)
Edit: I mis-read your post, but I take it you have the factory 16MB of ram?
So yeah, the same thing I said above still applies. 32MB will not fit into 16MB of RAM.