The "xsurftest" diagnostic tool, access the card directly (it doesn't use/need the xsurf.device).
You should have in output:
7/0.SYS:C> xsurftest
xsurf testprg V1.2 (13.12.1999)
Searching for xsurf card (VEN_ID=4626, PROD_ID=23)....found
Board address = 0xe90000
ISA Plug and Pray [ähm] Play setup...
01-CARD VendorID = 0x19808c4a SerNr=0x15eb CRC==x54
Setup PNP card...
Searching for RTL8019 at 0x300...found!
Testing 16bit memory...ok!
Ethernet address = 0:c0:26:xx:97:14
Chip is in PnP mode
Chip is using half-duplex mode
Chip is using IOBase 0x300 and IRQ 3
IRQ / Loopback / cable connection test in progress:
IRQ received ok.
Packet send......via TP!
After Thomas suggestions, try reseatting the only PLCC socketed IC (carefully and only if you know what you are doing) and clean the Zorro contacts.
Do you have some output from the test app or nothing?