Hi,
the problem could be related to the protected URLs. If they are enabled, WebRatio generator appends to all the URLs of the application pages with a not null query string a checksum postfix (for example: &CRC=988602091), which prevents malicious users from issuing HTTP requests with invented parameter values. If the URL of a request wrongly does not end with the CRC code, the "Invalid Request" message error will appear, informing the user that the control code parameter is missing.
In your case:
- did you enable the protected URL ? You can check it in the Properties Panel of the Project -> Security tab -> "Protect URL" property and "Digest Type" property.

- if the protect URL is enabled, you could try to fully generate your Web Project and check if the URLs end with the CRC code.
About the report compilation problem:
- did you get any errors when you compile the report with iReport ? What is the error message ?
- what do you mean by saying that the generated file can not be opened ?