If you can't find a ZD with FW 9 or higher to have it upgrade the AP there are things you can try. First try changing the FTP server. I think you've got the fwupdate.ruckuswireless.com server there. Change that to fwupdate1.ruckuswireless.com (notice the 1)
If that doesn't work. I'd suggest you download the FW from the RW page, start a TFTP server on your LAN and upgrade it that way. You'll need a control file. I don't know exactly how these look like for ZoneFlex but if you go by how MediaFlex controll file looked like it would be something like below.
same as above
First you specified the TFTP servers address
then the name of the file to be uploaded
then the size of the file in bits
Save that in a fwcntrl7363.rcks file or similar. I've never updated a ZF AP this was, but I guess it should work.