I have set the PreferredToolSize on my ribbon groups and on each individual tool to Large and the CanCollapse property on my ribbon groups to False. When my ribbon first displays, everything is correct. However, once I add another contextual tab group, the tool sizes all change and I have a bunch of small tools in my groups. What is causing the tool sizes to change? Is there something I can do to keep them all large?
Try setting the MinimumSizeOnRibbon for the tools instead of the PreferredSizeOnRibbon. This will force the tools to always display Large.
I forgot to mention that I am setting the MinimumSizeOnRibbon property to large as well. The tools display properly initially. After the ribbon is changed, the tools lose their sizes.