The Prototyping phase of the BAIKAL-GVD project has been started in April 2011 with the deployment of a three string engineering array which comprises all basic elements and systems of the Gigaton Volume Detector (GVD) in Lake Baikal. In April 2012 t
he version of engineering array which comprises the first full-scale string of the GVD demonstration cluster has been deployed and operated during 2012. The first stage of the GVD demonstration cluster which consists of three strings is deployed in April 2013. We review the Prototyping phase of the BAIKAL-GVD project and describe the configuration and design of the 2013 engineering array.
We present the results of a new analysis of data taken in 1998-2002 for a search for high-energy extraterrestrial neutrinos. The analysis is based on a full reconstruction of high-energy cascade parameters: vertex coordinates, energy and arrival dire
ction. Upper limits on the diffuse fluxes of all neutrino flavors, predicted by several models of AGN-like neutrino sources are derived. For an ${bf E^{-2}}$ behavior of the neutrino spectrum, our limit is ${bf E^{2} F_{ u}(E) < 2.9 times 10^{-7}}$ cm${bf ^{-2}}$ s${bf ^{-1}}$ sr${bf ^{-1}}$ GeV over a neutrino energy range ${bf 2 times 10^4 div 2 times 10^7}$ GeV. This limit is by a factor of 2.8 more stringent than a limit obtained with a previous analysis.
