Hi!
FYI: the last git commit (6ea973b79ef8f53a250313f34218680a7b5fb1b4) in the firmware directory has fixed the problem that for certain cards, the first APDU was transmitted together with the ATR in the first GSMTAP message.
I am currently trying to fix some other bugs (particularly the known issue regarding high-speed cards) and will make a v0.6 firmware release once that is done.
Regards, Harald