Reproduce steps:
1. Stage JRE 170- b147 with this guide http://j2se.sfbay.sun.com/web/bin/view/Deployment/JavaFXJREStaging
2. Set InstallerXmlUrl with URL to customized xml
3. launch iftw installer with SPONSORS=0
Expected: it install jre and fx runtime.
Actual: It prompts an error "Download file xxx is corrupted"

I tested with fx runtime b41. fx-runtime-2.0.exe (created with lzma), xml file and error screen shot were uploaded