Vray RT engine problems with Maya 2013

[WHITE_ENRIQUE]

I had used VRay for Maya 2011 and 2012 and never experienced any problems, however, recently I installed Maya 2013 and downloaded the corresponding VRay version.
I can render without any problems, however, when I attempt to use the RT engine, I get all kinds of problems, such as:
1. Vray frame buffer fails to update the image when I move the scene or change anything in the material.
2. At times, it causes Maya to stop working.

The following appears in the Script Editor
// Warning: [SettingsEXR] No image writer specified. //
// Warning: [SettingsTGA] No image writer specified. //
// Warning: [SettingsTIFF] No image writer specified. //
// Warning: [SettingsSGI] No image writer specified. //
// Warning: [SettingsJPEG] No image writer specified. //
// Warning: [SettingsPNG] No image writer specified. //
// Warning: Scene is empty. //

Do anybody has an idea of what this is about?
Please help
EW

[t.petrov]

Can you post the full log from Maya and V-Ray Standalone?
Are this problems scene specific or do they happen for all scenes?
What version of V-Ray are you using and on what OS?