Therefore we are currently implementing them on all UNIX platforms. We expect that colours will be available in version 3.2 which is planned to be released in the fall. You are probably right. However, if you do not tell us more specifically which bugs you frequently experience then we will never know. Bug reports can be submitted by means of an online fill-out form .
Reproducable bugs are most likely to get fixed.
Layout of diagrams is dominated by the features of the alignment facilities in the tool. The Align-menu has a lot of general alignment features, where grid in principle can be imitated. It is not clear how grid and align could co-exist. We have not worked on this and is open for discussion. The error messages are taken directly from the SML compiler which is used to parse a CPN model.