I have a simple script HelloWorld.csx, printing out Hello World to the console.
When executing the script with caching enabled, a ScriptCompilationException is thrown and the script does not get executed. But the compiled assembly gets written to the .scriptcs_cache directory:

scriptcs HelloWorld.csx -cache

ERROR: Script compilation failed. [ScriptCompilationException] Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.

When issuing the same command a second time, the script executed properly from the cached assembly:

scriptcs HelloWorld.csx -cache

Hello World