The reason you can't access it is because your PC network adapter isn't communicating with the 1522 and isn't automatically getting the correct IP info to do so.
This not correct - I had 2 computers running xp x64 and W7 x64 wired to the DAP-1552 configured (using WPS button) in bridge mode to a DIR-655 router. The connection worked just fine, I was able to see all other PC's and devices on my network, access internet, etc.... The problem is that I was not able to see the DAP 1552 from anywhere and access its configuration menu. After a "factory" reset, the configuration setup to my router was preserved since I did not have to use the WPS buttong again.
I could not see its MAC address in the arp table either.
I tried again to reset it and configured the PC wired to it with 192.168.0.99:
IP address: 192.168.0.99
Subnet: 255.255.255.0
Gateway: 192.168.0.50
This time it worked!
I tried the above settings several times before with same gateway and various other IP's but it never worked. I think the .99 IP made the difference but I don't understand why.
In the configuration menu I changed the DAP LAN to DHCP, connected it to my router and now it is working again in bridge mode and I can access it by its new 10..199 IP address or http://dlinkap from any PC, wired or not, responds to pings, can see it in arp cache and everything is normal.
The configuration with the .99 IP seems to have been recomended by Dlink before since I found it in this post:
http://www.paraesthesia.com/archive/2010/05/04/connect-to-the-d-link-dap-1522-access-point-configuration-manually.aspx
The remarks regarding DHCP are right cause since I tried many times with static IP and .50 gateway before trying the .99 IP
Plus, the use of the gateway does not make sense either since both are configured with static IP's and physically on the same network. I can confirm that the pings and attempts to access the DAP were using the right adapter as shown also in the routing table. I even tried it with all other network adapters disabled on the PC to make sure.