Annoying issue after a new SW12 install.

I cannot configure a dimension within a sketch by right-clicking it to bring up the configuration table; the option is no longer available in the right-click window. How can this option be resurrected? It's a nuisance to be forced to exit the sketch every time to configure a dimension.

I'm not sure if 'configuration table' is the proper term, so to clarify here's an example of what I mean:

http://i.imgur.com/KveT3Fs.png

Here is what I see when I right click a dimension, note no 'configure dimension':

http://i.imgur.com/BQFT7ZU.png

Here are my Customize Menu settings. 'Configure dimension' is absent, not showing up as unchecked, but it looks like the window may be cut off by the boundary of the screen?

http://i.imgur.com/hC0sjxa.png

I can still summon the configuration table by right-clicking the sketch in the feature tree and choosing 'configure feature.' I can also double-click the sketch in the feature tree to show the dimensions and then right-click, but it sometimes doesnt show certain dimensions seemingly arbitrarily. But both ways require me to exit the sketch and either remember dimension names or rename them something memorable.

Help please and thanks!