fixed compiler's errors

wrap/gl/pick.h

@@ -165,6 +165,7 @@ public:
 		}
 		
 		delete [] buffer;
+		return result.size();
 	}
 
 };

wrap/gl/picking.h

@@ -75,6 +75,7 @@ int Pick(	const int & x, const int &y,
 
 		GLint viewport[4];
 		glGetIntegerv(GL_VIEWPORT,viewport);
+		glPushAttrib(GL_TRANSFORM_BIT);
 		glMatrixMode(GL_PROJECTION);
 		glGetDoublev(GL_PROJECTION_MATRIX ,mp);
 		glPushMatrix();
@@ -114,7 +115,7 @@ int Pick(	const int & x, const int &y,
 			std::advance(ei ,H[ii].second);
 			result[ii]=&*ei;
 		}
-
+		glPopAttrib();
 		delete [] selectBuf;
 		return int(result.size());
 	}

wrap/io_trimesh/import_dae.h

@@ -271,6 +271,7 @@ class ColladaMesh    : public vcg::tri::TriMesh< std::vector<ColladaVertex>, std
 				++fp;
 			}
 			assert(fp==m.face.end());
+			return E_NOERROR;
 		}
 		
 		static DAEError	OldLoadPolygonalListMesh(QDomNodeList& polylist,ColladaMesh& m,const size_t offset,InfoDAE* info)

wrap/io_trimesh/import_obj.h

@@ -92,6 +92,7 @@ Initial Working version coded by Buzzelli.
 #include <vcg/complex/trimesh/allocate.h>
 #include <wrap/io_trimesh/io_mask.h>
 #include <wrap/io_trimesh/io_material.h>
+#include <vcg/space/color4.h>
 
 #include <fstream>
 #include <string>