Problem with WBR-3406TX Router

Hello everyone! I have a big problem trying, for the first time, to setup a router. I got a LevelOne WBR-3406TX router. I connected it to my cable broadband modem and turned it on. I was able to get into the its settings (browsing to 192.168.123.254) and started setting up the basic stuff (SSID etc...), although I did that via the wireless connection on my laptop, which I realize now was my first mistake, I then went and changed the security settings to WPA2 and set a new password I was then asked to reboot my router so I disconnected it from the power and reconnected, it seemed to work fine for a couple minutes but then the STATUS and WAN lights went off and my my modem stopped recognizing the router (the PC-LINK light on the modem went off too). I can no longer get to the router's settings (even when I connect it via LAN to my PC). I tried rebooting both the modem and the router to no avail. The only lights that are on in my router are the WLAN and the LAN~4 (although nothing is connected to the 4th lan port). I tried to follow the manual's instructions on how to reset it and it just won't reset. From what I understood there are two ways to do it, the first is to simply press and hold the reset button for several seconds until the router's lights start flashing which never happens even after a minute... The second is to disconnect the router from power and press the reset button, then reconnect it and press and hold the reset button again until the lights start flashing, but this doesn't work either (the same lights - WLAN and LAN~4 - stay on, like they're stuck or something).

Here's the manual for the router (RESET instructions are on page 76):
http://download.level1.tw/level1/m [...] TX(EN).pdf

Anyway, after several failed tries to reset this thing I gave up... My modem still won't recognize it anymore and it's just stuck on those lights every time I connect it to power. I hope someone can help me figure out why it stopped working so suddenly and maybe give me better instructions on how to correctly reset it.

Thanks in advance!