I installed the maitenance build using the link you provided. After installation an instance of regular Ready API was launched automatically. I encountered absolutely the same issue as I described yesterday. Structure <abc: State></abc: State> didn't make any difference. This tag was deleted anyway.
Then I manually ran another instance of Ready API Snapshot from Windows menu. The behavior was slightly different: an Error showed up with following text: Do you want to recreate a default message from the schema? I clicked No and all the fields dissapeared from Form view but xml file wasn't blanked out. Running my service created an error.
Then I closed current Ready API Snapshot instance and launched another one. This time I answered Yes to the error message. It set all the fields to "?" value but kept the structure in both Form and XML views.
I think I will stick with regular Ready API rather than Snapshot. If I don't switch to Form view, Ready API allows me to run services based on an XML file.
The behavior you describe is very strange (several Ready! API instances shouldn’t work differently). Could you please contact our Ready! API Customer Care Team ( http://support.smartbear.com/product-list/ ) to analyze this behavior and to come to the solution?