i guess where it says "open" is where you want to put a jumper.
Other way around, a pair of pins with jumper fitted are "closed" by the jumper.
Some people get messed up with "open circuit" having something to do with jumpers being "open", but this is not the case.
Also I agree, set it to 4MB with jumpers & the PCMCIA will most certainly work...I've tried it myself :-)
PZ.