I couldn't find the answer in the manual or in the search...

it might not be possible. Is there a way for me to see how much ram I'm currently using?

In the load menu you can see Wave Free and Seq. Free , so check your ram when it's empty and just subtract your mem from that.
There might be an even easier way but i'm not sure at the moment.
Greetz...

When you hit 'window' in record mode it tells you how much sample time you currently have left with a memory meter giving you a visual representation of how much RAM you currently have left. It doesnt give you a numerical figure though.