A nasty little bug which influenced (i.e., screwed up) the labeling of some models (specifically, models with the same number of parameters which are run sequentially), and in turn things like 'model averaging' across those models, has been fixed. You're encouraged to install the latest version of MARK as soon as you can.
You can grab the MARK installer here: http://www.phidot.org/software/mark/downloads/