Online communication is sometimes the best way to diagnose problems, but it is not always available, for example you might be in different time zone that people you want to chat with or simply the people are busy in this time. You can try asking here, but if you do not get any reaction, you should retry later or try to use mailing list.
You are very welcome to #gammu at irc.freenode.net. Feel free to ask there your questions. If you don't get the answer immediately, don't worry and patiently wait until someone answers. The channel is low volume and it may take a while until someone notices your question.
You can also find a robot called like CIA-42, which just sends a notifications there about every commit made to the Gammu source repository.