I am expereinced in SE15 yet very new to ST4. I successfully ran through a couple ST4 tutorials yet I am now having problems even when I go back and repeat the same tutorials.
My problem is the same for the Ordered and Sychronous environments. Sketch and model dimensions cannot be changed. I click on the dimension to obtain the small box indicating the dimentional value. When I type in the desired value and press enter, the numeric value for the dimension changes and is displayed with an underline. The actual size of the element does not change.
Again, this problem is the same for both sketches in the Ordered environment and changing a size of a model feature in the Synchronous environment.
Sounds like your dimensions are being placed as Driven/Unlocked which means that the geometry is the driver. The underline means that you have just overriden the actual dimension value. Click on a dimension and look for a lock on the edit bar. Make sure it is shown as locked.