I've been trying to learn MacRuby by following " MacRuby - The Definitive Guide" and have encountered problems with the code given in Chapter 7. My system is running MacOS X 10.7.3 and Xcode Version 4.3.2 which were installed on a clean hard drive so there are no remnants of earlier software present to confuse the issue. I'm running MacRuby from the nightly build 03/24 which I installed yesterday - I was previously running an earlier version. Because I am unable to distinguish Xcode problems from MacRuby (or Definitive Guide) problems I'm posting this problem with both communities. Here is a description of the problem I'm having. Chapter 7 includes a table, beginning on pg 129, which is intended to contain Text Field, Combo Box, and Button cells. I am unable to create the latter two cell types following the instructions given. In the case of the Combo Box, I can identify the cell as containing an NSComboBoxCell using the Custom Class on the identiy tab. When I switch to the attributes tab the cell is still identified as Text Field and so I am unable to create the labels for the combo box. Also, the cell field displayed in the table does not have the up/down arrows - no visual cue that there is a list of choices available. The problem with the NSButtonCell is easier to describe as the choice is not available through the Custom Class. If I type it into the field it is replaced with the default NSTextCell. I've loaded the project for Chapter 7 from Matt's Git site and can view the proper behavior for both columns when I load it into Xcode. This code also builds (although with three warnings - none related to the table) and runs. This code can be used to demonstrate the expected response. Any suggestions? thanks in advance, Rick