mn-100 xpsp2 base station and win 98se

My xp sp2 computer and the win 98se computer are both able to connect to the
internet, but are unable to see each other on the network since I set the xp
computer as the base station. The computers are set to share files and
printers, and they are both set to use the the same workgroup as when the
win98 computer was set as the base station. I ran the xp network set up
utility to program I downloaded for the mn-100 and updated the firmware but
both computers are unable to browse the network. What is wrong? Also, how far
can the 98se computer be phisically located from the mn-100. It all really
began when my wife moved the 98 computer upstairs (it was set as the base
station originally) and that shut down everything including internet
connectivity. Our sons Mac10 had been able to use that connection without any
problems but not the win98 computer. I assumed that was because it was the
base station. So I tried to set up the xp computer as the base station. Then
the problems started. Please help.