Solid Edge Simplified subassemblies are not activated

In this example, the customer has their "Assembly Open As" options for Medium Assemblies set as follows:

When they open an assembly as a Medium Assembly they find that the simplified subassemblies are not loaded as active. 

The problem they then have is that they cannot select any geometry from these assemblies when using the Measure tools.

The only way to get round this seems to be by changing ‘Assembly Open As’ – Subassembly simplification to "Use all designed".

This is working as designed. 

The simplified subassemblies are presumed to be mostly for context, so only their display data is loaded.  The intention is to always load only what is needed, which improves performance and allows for working with larger assemblies.  If locate is needed - for example, in order to take measurements - just right-click on the simplified subassembly and select Activate.  Solid Edge will load more data about the simplified state and allow locate, whilst keeping the subassembly in a mostly-inactive state.  That is, Solid Edge will load the subassembly document, but stop short of loading any of its components. 

Therefore, there is no need to change  ‘Assembly Open As’ – Subassembly simplification to "Use all designed".