Wil,
I reproduced this and logged it to be fixed. Also, it looks like a generic issue with the debugger - the text in the sText doesn't need to be Unicode to crash...
Code:
Use Windows.pkg
Procedure Test
String sText
Move "Wil hat den Debugger zum Absturz gebracht" to sText
Showln "put a break point on this line"
Showln sText
End_Procedure
Send Test
Inkey WindowIndex
Edit: Interestingly enough, it only crashes if the string is empty. If you edit it to any other value, including Unicode text, its fine.