I have compiled the ushare for SMC WAPS-G. You can start it if you have MGBR4v3 firmware in the following way. I assume that you know how telnet into your box.
1. Download the files onto your internal hardware drive. For example, store them under /mnt/C/ushare
2. Create a link to libintl.so.1.0.1 using the following command:
ln -s libintl.so.1.0.1 libintl.so.1
3. Modify ushare.conf to reflect your shared folders
4. Add the following line to your autoexec on the hard drive
LD_LIBRARY_PATH=/mnt/C/ushare /mnt/C/ushare/ushare -f /mnt/C/ushare/ushare.conf
Your upnp server should automatically start afterwards.