What settings are you using on your wireless router and the DAP-1522 in order to get them working?
I also have a DIR-655/DAP-1522 setup (actually 2 DAP-1522s) that I managed to make them work. Here are my settings:
DAP-1522 (items marked with * are not configurable as they were grayed out):
--802.11 Band: 2.4GHz/5GHz*
--802.11 Mode: Mixed 802.11 abgn*
--Wireless Channel: 36* (note 1)
--Transmission Rate: Best(automatic)*
--Channel Width: auto 20/40 MHz
--Security Mode: WPA personal
--WPA Mode: WPA2 only
--Cipher Type: AES
--WPS: disabled
--Wireless MAC Cloning: disabled
The setting on DIR-655 are:
Hardware Version: B1 Firmware Version: 2.00NA
802.11 Mode : 11gn
Channel Width : 20/40 MHz
Channel : 2
WISH : Inactive
Wi-Fi Protected Setup (WPS): Disabled
Note: I originally had my WPS setting on DIR-655 as "Enabled" and had all sorts of problems (I guess I forgot to turn it off when I tried to auto-config the DAP-1522). But I think you need to manually config it if you want to set it up as a bridge.
I have my full posting at DSLReports.com. You can check it out there if you are interested.
http://www.dslreports.com/forum/r25222278-Help-Me-Low-performance-for-DAP-1522-multiple-units-
Good luck with your endeavor. I think it's a pain to set them up if you want to use the DAP as a bridge. But if you manage to get them working, they can deliver pretty good performance. I have both my DAPs running at 100+mbps now.