Just updated to the 4.3.5.6299 build from 4.3.1, now I get this:

var query =
                Query.All<DocEntity>().Select(
                    q =>
                    new DocEntityInfo()
                        {
                            Caption = q.Name,
                            Id = q.Id,
                            Name = q.SysName,
                            Description = q.Description,
                            EntityTypeId = q.EnEntityType.Id,
                            EntityTypeName = q.EnEntityType.SysName,
                            LinkedEntitySysName = q.LinkedEntity != null ? q.LinkedEntity.SysName : null,
                            OwnerEntitySysName = q.OwnerEntity != null ? q.OwnerEntity.SysName : null,
                            FieldsInfo = fieldsDict.ContainsKey(q.Id) ? fieldsDict[q.Id] : new List<DocFieldInfo>(),
                            NumeratorInfo =
                                numeratorsDict.ContainsKey(q.Id) ? numeratorsDict[q.Id] : new List<NumeratorInfo>(),
                            Interfaces = interfacesDic.ContainsKey(q.Id) ?
                                interfacesDic[q.Id] : new Dictionary<Guid, string>()
                        });

            _captions = null;
            return query.ToList();

The Exception: Type 'System.Collections.Generic.Dictionary <system.guid,system.collections.generic.list <werp.controller.repository.cache.valueobjects.docfieldinfo="">>' is not supported.

[NotSupportedException: Type 'System.Collections.Generic.Dictionary<System.Guid,System.Collections.Generic.List<Werp.Controller.Repository.Cache.ValueObjects.DocFieldInfo>>' is not supported.]
   Xtensive.Sql.TypeMappingCollection.GetMapping(Type type) in c:\Temp\DataObjects.Net\Xtensive.Sql\Xtensive.Sql\ValueTypeMapping\TypeMappingCollection.cs:89
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.VisitParameterAccess(Expression e, Boolean smartNull) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:83
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e, Boolean smartNull) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:69
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:60
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.VisitMethodCall(MethodCallExpression mc) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:308
   Xtensive.Core.Linq.ExpressionVisitor`1.Visit(Expression e) in c:\Temp\DataObjects.Net\Xtensive.Core\Xtensive.Core\Linq\ExpressionVisitor{TResult}.cs:106
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e, Boolean smartNull) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:72
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:60
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.VisitConditional(ConditionalExpression expression) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:255
   Xtensive.Core.Linq.ExpressionVisitor`1.Visit(Expression e) in c:\Temp\DataObjects.Net\Xtensive.Core\Xtensive.Core\Linq\ExpressionVisitor{TResult}.cs:94
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e, Boolean smartNull) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:72
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:60
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.VisitUnary(UnaryExpression expression) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:110
   Xtensive.Core.Linq.ExpressionVisitor`1.Visit(Expression e) in c:\Temp\DataObjects.Net\Xtensive.Core\Xtensive.Core\Linq\ExpressionVisitor{TResult}.cs:63
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e, Boolean smartNull) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:72
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:60
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.VisitLambda(LambdaExpression l) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:348
   Xtensive.Core.Linq.ExpressionVisitor`1.Visit(Expression e) in c:\Temp\DataObjects.Net\Xtensive.Core\Xtensive.Core\Linq\ExpressionVisitor{TResult}.cs:109
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e, Boolean smartNull) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:72
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Visit(Expression e) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:60
   Xtensive.Storage.Providers.Sql.Expressions.ExpressionProcessor.Translate() in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\Expressions\ExpressionProcessor.cs:54
   Xtensive.Storage.Providers.Sql.SqlCompiler.ProcessExpression(LambdaExpression le, List`1[] sourceColumns) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\SqlCompiler.Helpers.cs:72
   Xtensive.Storage.Providers.Sql.SqlCompiler.VisitCalculate(CalculateProvider provider) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\SqlCompiler.cs:105
   Xtensive.Storage.Rse.Compilation.Compiler`1.Compile(CompilableProvider cp) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Rse\Compilation\Compiler.cs:75
   Xtensive.Storage.Providers.Sql.SqlCompiler.VisitSelect(SelectProvider provider) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Providers.Sql\SqlCompiler.cs:0
   Xtensive.Storage.Rse.Compilation.Compiler`1.Compile(CompilableProvider cp) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Rse\Compilation\Compiler.cs:105
   Xtensive.Storage.Rse.Compilation.Compiler`1.Xtensive.Storage.Rse.Compilation.ICompiler.Compile(CompilableProvider provider) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Rse\Compilation\Compiler.cs:44
   Xtensive.Storage.Rse.Compilation.CompilationContext.Compile(CompilableProvider provider) in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Rse\Compilation\CompilationContext.cs:143
   Xtensive.Storage.Rse.<GetEnumerator>d__4.MoveNext() in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage.Rse\RecordSet.cs:69
   System.Linq.WhereSelectEnumerableIterator`2.MoveNext() +87
   Xtensive.Core.<Batch>d__20`1.MoveNext() in c:\Temp\DataObjects.Net\Xtensive.Core\Xtensive.Core\Extensions\EnumerableExtensions.cs:498
   Xtensive.Core.<ApplyBeforeAndAfter>d__28`1.MoveNext() in c:\Temp\DataObjects.Net\Xtensive.Core\Xtensive.Core\Extensions\EnumerableExtensions.cs:594
   Xtensive.Storage.<ToTransactional>d__0`1.MoveNext() in c:\Temp\DataObjects.Net\Xtensive.Storage\Xtensive.Storage\TransactionalExtensions.cs:327
   System.Linq.<SelectManyIterator>d__14`2.MoveNext() +399
   System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) +327
   System.Linq.Enumerable.ToList(IEnumerable`1 source) +58
   Werp.Controller.Repository.Cache.EntityList.RefreshCache() in D:\Home\Docs\Visual Studio 2010\Projects\Platform\Werp.Controller.Repository\Cache\EntityList.cs:114
   Werp.Controller.Services.BaseCache`1.get_Cached() in D:\Home\Docs\Visual Studio 2010\Projects\Platform\Werp.Controller.Repository\BaseCache{T}.cs:31
   Werp.Controller.Services.Navigation.Entities.GetEntityNodes(Guid entityTypeId, String nodeId) in D:\Home\Docs\Visual Studio 2010\Projects\Platform\Werp.Controller.Services\Navigation\Entities.cs:168
   Werp.Controller.Services.Navigation.Entities.GetNodes(String parent) in D:\Home\Docs\Visual Studio 2010\Projects\Platform\Werp.Controller.Services\Navigation\Entities.cs:63
   Werp.View.Ext.TreeService.GetNodesString(String treeName, String nodeId) in D:\Home\Docs\Visual Studio 2010\Projects\Platform\Werp.View.Ext\TreeService.cs:61
   Werp.View.Ext.TreeLoader.ProcessRequest(HttpContext context) in D:\Home\Docs\Visual Studio 2010\Projects\Platform\Werp.View.Ext\Handlers\TreeLoader.ashx.cs:36
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +100
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75