Dear Swift,
The gsmmap branch that you are using was created to allow users
to submit their own traffic to
gsmmap.org and it's not meant to
be used as a mass interception tool.
If you use ccch_scan _and_ specify your ARFCN _and_ specify your TMSI
_and_ your network does not use encryption, then you will probably be
able to see your SMS in wireshark. Please note that the TMSI may be
re-allocated by the network at any time.
To make testing easier I suggest you to use a second Osmocom phone
running the official mobile application/firmware and set the "stick"
option in the configuration, so the ARFCN will not change.
Cheers,
LM