We are working on a much better system. 

+ In the code editor there will also shortly be right click "Add Watch" and "Add modifiable watch" menu items which will simply add the highlighted text to the "WhenHit" statement either as {myvar} or {myvar=?}. This uses the eixsting functionality but will be less clicks.

This isn't ideal but here are some things you can do at the moment...

Visual Micro always #defines VM_DEBUG when debug is enabled. (There is also the _DEBUG setting in the project properties which can be configured with different values).

You can return anything you like in a watch expression by calling your own method that calls code conditionally compiled using VM_DEBUG.

Your breakpoint Conditions can also call methods protected by VM_DEBUG in your own code for example WhenTrue=MYMACRO or function

Using VM_DEBUG or _DEBUG without breakpoints doesn't give much debug support other than allowing you to use the toolbar to easily switch between Release and Debug builds.