Hi Belá
I'm also having trouble with the wifi in this beta. Somehow there are some realtek firmware included in the kernel base as my Edimax wifi dongle is found and piCore thinks that it can be used. However, when trying the dongle by "sudo wifi.sh" finds the available networks but it is unable to connect.
dmesg output before firmware-rltwifi.tcz is installed:
[   29.816310] rtl8192cu: Chip version 0x10
[   30.189692] rtl8192cu: MAC address: 80:1f:02:d3:53:1a
[   30.189744] rtl8192cu: Board Type 0
[   30.189980] rtl_usb: rx_max_size 15360, rx_urb_num 8, in_ep 1
[   30.190156] rtl8192cu: Loading firmware rtlwifi/rtl8192cufw_TMSC.bin
[   30.190376] usb 1-1.4: Direct firmware load for rtlwifi/rtl8192cufw_TMSC.bin failed with error -2
[   30.190485] usb 1-1.4: Direct firmware load for rtlwifi/rtl8192cufw.bin failed with error -2
[   30.190504] rtlwifi: Loading alternative firmware rtlwifi/rtl8192cufw.bin
[   30.190517] rtlwifi: Firmware rtlwifi/rtl8192cufw_TMSC.bin not available
[   30.192065] ieee80211 phy0: Selected rate control algorithm 'rtl_rc'
[   30.197117] usbcore: registered new interface driver rtl8192cu
However lsmod shows that some driver for the wifi dongle is loaded:
tc@box:~$ lsmod
Module                  Size  Used by    Not tainted
rtl8192cu              93939  0
rtl8192c_common        63420  1 rtl8192cu
rtl_usb                13144  1 rtl8192cu
rtlwifi                86632  3 rtl8192cu,rtl8192c_common,rtl_usb
mac80211              356047  3 rtl8192cu,rtl_usb,rtlwifi
cfg80211              216968  2 rtlwifi,mac80211
rfkill                 18713  1 cfg80211
spi_bcm2708             5430  0
i2c_bcm2708             5284  0
tc@box:~$
and iwconfig shows that I have wifi:
tc@box:~$ iwconfig
wlan0     IEEE 802.11bgn  ESSID:off/any
          Mode:Managed  Access Point: Not-Associated   Tx-Power=0 dBm
          Retry short limit:7   RTS thr=2347 B   Fragment thr:off
          Power Management:on
dummy0    no wireless extensions.
lo        no wireless extensions.
eth0      no wireless extensions.
tunl0     no wireless extensions.
tc@box:~$
After downloading the "firmware-rtlwifi.tcz" the dmesg looks better:
[   29.803331] rtl8192cu: Chip version 0x10
[   30.117837] rtl8192cu: MAC address: 80:1f:02:d3:53:1a
[   30.117888] rtl8192cu: Board Type 0
[   30.118157] rtl_usb: rx_max_size 15360, rx_urb_num 8, in_ep 1
[   30.118328] rtl8192cu: Loading firmware rtlwifi/rtl8192cufw_TMSC.bin
[   30.123219] ieee80211 phy0: Selected rate control algorithm 'rtl_rc'
[   30.143076] usbcore: registered new interface driver rtl8192cu
the lsmod is now:tc@box:~$ lsmod
Module                  Size  Used by    Not tainted
rtl8192cu              93939  0
rtl8192c_common        63420  1 rtl8192cu
rtl_usb                13144  1 rtl8192cu
rtlwifi                86632  3 rtl8192cu,rtl8192c_common,rtl_usb
mac80211              356047  3 rtl8192cu,rtl_usb,rtlwifi
cfg80211              216968  2 rtlwifi,mac80211
rfkill                 18713  1 cfg80211
spi_bcm2708             5430  0
i2c_bcm2708             5284  0
tc@box:~$
And it still can scan the network and find the available networks, however, it also can't connect (so it is not better after using the rtl-firmware package):
Select Wifi Network
    ESSID                         Enc   Qual    Channel Type
 1. linksys                        on    70      11     WPA
 2. Steens 2.4GHz                  on    26       6     WPA
Enter selection ( 1 - 2 ) or (q)uit: 2
Enter password for Steens 2.4GHz (8 to 63 characters): smiley12
Sending credentials to requested access point Steens 2.4GHz..
udhcpc (v1.22.1) started
Sending discover...
Sending discover...
Sending discover...
No lease, failing
Failed to connect.
tc@box:~$
 
So unfortunately I can't get this very popular wifi dongle to function with this kernel.
I will report on my ralink wifi in a moment.
Steen