According to the documentation I found here, just plug in an antenna and you are good to go (bold text is mine):
Connect an external antenna to the Omega’s male surface-mounted U.FL connector. An external antenna can be used to extend the range of WiFi connectivity or provide a very directional signal. If a U.FL antenna is plugged in, it will be used as the default antenna, no setup required.
I know this is an old topic, but I think it might be resolved now.
I was also seeing this problem affecting GPIO13 (RX0). Since that GPIO belongs to the console serial port, it meant that if I ever rebooted with my console serial adapter connected, the Omega would not boot. At that point, the only way to get control of the Omega would be to disconnect the serial adapter and then power cycle it.
I am happy to report that my issue [at least] has been fixed with the firmware release 0.1.9. After installing that firmware, my device now reboots with the serial port adapter connected. So maybe these issues are also resolved for the other GPIOs mentioned above? Perhaps someone else can confirm.
Is it possible to have a second network (like a guest network, for example) running on the Omega's access point link, using its own SSID? I have been trying to do that, but have not succeeded yet. Mainly, I have become an expert in recovering an Omega that has lost its wireless connection after each of my new experiments.
Is the Omega2 capable of acting as an access point with multiple SSIDs? I would like to create a secondary SSID for testing purposes that would not wipe out the primary connection.
OK, I get it now.
The 'reset' button on a dock has no direct connection to the processor 'reset' signal. Pressing this button is not expected to affect the processor's 'reset' input. That's why there is no electrical connection between the two.
The 'reset' button on the dock is merely a GPIO input to the Omega software. If that software is misbehaving, the button presses may do nothing. In fact, this was the case recently and explains your request to update to the latest image.
In contrast, asserting a reset signal in an embedded system is one of the very few things that absolutely cannot be ignored by the components in that system.
In my opinion, 'reset' is an unfortunate choice of name for the dock's button, but it's just an opinion.
Thanks for the prompt response!
@Luciano-S. My firmware would appear to be up to date:
root@Omega-AFE5:/# oupgrade --check
Device Firmware Version: 0.1.7 b139
Checking latest version online...
Repo Firmware Version: 0.1.7 b139
Comparing version numbers
Device firmware is up to date!
I will go read the other announcements now.
@dgluhak4 Success! After getting control of the console serial by adding the wires to the Power Dock, I found that typing "wifisetup" would allow me to re-enter the required data for the Omega2+ to re-establish the wireless connection to my router. My system is responding normally again, and I can finally get back to the Omega configuration page:
Here is how I added the wires:
@Robin-Hodgson Well, crap. I take it back: grounding the RST signal to the GND signal on the Power Dock expansion connector seemed to help, but it does NOT reset the Omega to factory defaults. I finally got a console serial connection to the power dock by soldering some wires to the header where the Omega2+ mounts. Poking around in the file system makes it very clear that the Omega is not back to what came from the factory. For example, the file /etc/config/wireless is not reverted back to the original version since it contains references to the router in my house. Or maybe I don't need factory defaults, I need a reflash of the entire factory firmware so I can start over. Is that possible?
My power doc expansion board is not responding to the RESET button, as per the documentation located here.
I took a multimeter and ohmed the connection between all of the the reset button pins and the RST signal that is available on the dock's expansion connector. There is no connection. If I ground the RST pin on the expansion header, the Omega reset. If I push the button, nothing happens.
Reading other threads on this forum, it would appear that I am not the only person affected by this. Is it possible that the Expansion Dock's reset pin is not functional, or at least not functioning as described in the documentation referenced above?
@Robin-Hodgson OK, some more progress. After reading a bunch of docs, it turns out that there is a simple explanation, although not a simple fix.
The Power Expansion board breaks out TX1 and RX1. However, those are NOT associated with the UART device in the Omega 2+ that is used to access the console. The console port is located on RX0 and TX0. Sadly, those connections are not available on a Power Expansion board.
I hooked my scope to TX0 on the Omega, and do I see it chattering away during the boot process.
My takeaway is that the Power Expansion board is not the board you want to get started with. It has no reset button, and it provides no console serial access to the Omega. If you make a mistake that involves losing the WiFi connection, the Power Expansion board will not be your friend anymore 
I will try to solder some wires to TX0 and RX0 because I'm still confused why a factory reset results in a system that puts out the default access point SSID again, but is not authenticating the default WiFi password.
@WereCatf I just ohmed the connection from the Omega RX/TX to the expansion board RX1/TX1. They are connected as one would expect.
My scope shows no serial activity during boot from the Omega.
@WereCatf I am connecting to the Power Expansion board TX1 and RX1 connectors. My assumption is that these signals connect to the Omega2 TX1 and RX1 signals, but I can't find a schematic for the power expansion board.
I am using a generic CP2012 USB to serial board, where I know that its TXO means TX Output and RXI means RX Input, so I am connecting CP2102TXO to Omega RX1, and CP2201RXI to Omega TX1. But like I said, I swapped them and it didn't help.
I just broke out the big gun: during boot, the oscilloscope shows no serial activity on the expansion board TX1 (or RX1, for that matter). When I type in my own serial terminal, I can see myself sending chars that arrive on CP2102TX0.
@WereCatf Tried that. Tried every baud rate between 9600 and 115200. Nothing. Should I be seeing boot messages spewing out of the serial port?
@WereCatf I am having the exact same problem with my Omega 2+: wifi is gone, taking all connectivity with it. I only have a power dock, so there is no ethernet available.
As per this thread, I tried connecting a USB serial port to the power dock's TX1 and RX1 pins. I get no response from the Omega2+. I know that my USB serial connection is wired for 3.3V, and I know that the serial converter board works.
I am pretty sure that the button on the power dock is not a reset button, but a button to manually tell the PMIC (power management IC) on the power expansion board to start working, as per the PMIC data sheet. That would explain why pushing it for 10 seconds didn't do anything resembling a reset operation.
I did make a bit of progress though. To get around the lack of a reset button, try the following:
At this point, I can now see the Omega2+ acting as a wireless access point again using its default SSID: Omega-XXXX.
Sadly, I cannot connect to the Omega via that access point. The authentication fails every time using the default password "12345678".
In addition, the serial port still doesn't work for me.
Am I missing something obvious here? It wouldn't be the first time...