Crash when resizing modded planet

• Ensure you have installed the latest version of SEToolbox installed. Visit latest release to verify.
• Ensure that the issue is reproducible for testing. You may be requested to provide a link to a test world if we cannot reproduce it with your information.
• Retrieve the Event Log from when SEToolbox crashed. Read the following instructions on retrieving the event log.

SEToolbox Version: SEToolbox 01.189.33 Release 1
SE Version: 01.189.41

SEToolbox crashed

Resized a modded planet with custom voxel / textures for trees. Will not crash for vanilla planets or modded planets that only use vanilla assets

Steps to Reproduce

Just try to resize a modded planet with custom voxel / textures for trees. It will crash

SEToolbox Event Log

`2019-03-10 15:33:59,431 [1] FATAL SEToolbox.Support.DiagnosticsLogging [(null)] - Unhandled Exception
Application: C:\Program Files (x86)\MidSpace\SEToolbox\SEToolbox.exe
CommandLine: "C:\Program Files (x86)\MidSpace\SEToolbox\SEToolbox.exe"
CurrentDirectory: C:\Program Files (x86)\MidSpace\SEToolbox
SEBinPath: C:\Program Files (x86)\Steam\SteamApps\common\SpaceEngineers\Bin64
SEBinVersion: 1.189.41
ProcessorCount: 6
OSVersion: Microsoft Windows NT 6.2.9200.0
Version: 4.0.30319.42000
Is64BitOperatingSystem: True
IntPtr.Size: 8
IsAdmin: False
CurrentUICulture: en-GB
CurrentCulture:
Times started total: 4
Times started since last reset: 4
Times started since game update: 3

Files:
2019-03-09T22:25:43.5686089+01:00 25,104,944 HavokWrapper.dll
2017-06-02T09:49:12.0000000+02:00 498,176 2014.2.17.1 HelixToolkit.Wpf.dll
2017-03-08T19:26:22.0000000+01:00 276,480 2.0.8.0 log4net.dll
2019-01-17T19:05:17.0459313+01:00 660,128 12.00.21005.1 built by: REL msvcp120.dll
2019-01-17T19:05:17.0459313+01:00 963,232 12.00.21005.1 built by: REL msvcr120.dll
2018-09-09T02:31:30.0000000+02:00 911,360 0.32.0.0 Octokit.dll
2019-03-09T22:25:49.8286016+01:00 78,384 1.0.0.0 Sandbox.Common.dll
2019-03-09T22:25:43.5915338+01:00 7,657,008 1.0.0.0 Sandbox.Game.dll
2019-03-09T22:25:43.5915338+01:00 422,960 1.0.0.0 Sandbox.Graphics.dll
2019-03-09T22:25:48.4199991+01:00 22,576 1.0.0.0 Sandbox.RenderDirect.dll
2019-03-01T06:56:52.0000000+01:00 1,323,008 01.189.33.1 SEToolbox.exe
2017-06-02T09:49:12.0000000+02:00 745 SEToolbox.exe.config
2019-03-01T06:56:48.0000000+01:00 62,464 1.0.0.0 SEToolbox.ImageLibrary.dll
2019-03-01T06:56:48.0000000+01:00 7,680 1.0.0.0 SEToolbox.ImageShaders.dll
2019-03-01T06:56:52.0000000+01:00 2,248,192 SEToolbox.pdb
2019-03-01T06:56:48.0000000+01:00 53,248 1.0.0.0 SEToolboxUpdate.exe
2019-03-09T22:25:43.5915338+01:00 489,008 3.1.0 SharpDX.Direct2D1.dll
2019-03-09T22:25:43.5925310+01:00 288,304 3.1.0 SharpDX.Direct3D11.dll
2019-03-09T22:25:43.5925310+01:00 269,872 3.1.0 SharpDX.dll
2019-03-09T22:25:49.2342932+01:00 139,824 3.1.0 SharpDX.DXGI.dll
2019-03-09T22:25:43.5935287+01:00 499,248 1.0.0.0 SpaceEngineers.Game.dll
2019-03-09T22:25:47.9446835+01:00 63,536 1.0.0.0 SpaceEngineers.ObjectBuilders.dll
2019-03-09T22:25:43.5935287+01:00 4,847,664 1.0.0.0 SpaceEngineers.ObjectBuilders.XmlSerializers.dll
2019-03-09T22:25:43.5935287+01:00 329,264 11.0.0 Steamworks.NET.dll
2019-01-17T19:11:11.7507959+01:00 250,656 04.28.51.07 steam_api64.dll
2019-03-09T22:25:43.5935287+01:00 323,632 1.0.102.0 System.Data.SQLite.dll
2013-03-09T18:25:10.0000000+01:00 39,936 2.0.20525.0 System.Windows.Interactivity.dll
2019-03-09T22:25:50.1274121+01:00 24,112 1.0.0.0 VRage.Ansel.dll
2019-03-09T22:25:50.8713497+01:00 68,656 1.0.0.0 VRage.Audio.dll
2019-03-09T22:25:43.5945257+01:00 501,296 1.0.0.0 VRage.dll
2019-03-09T22:25:43.5945257+01:00 1,377,840 1.0.0.0 VRage.Game.dll
2019-03-09T22:25:43.5945257+01:00 7,290,416 1.0.0.0 VRage.Game.XmlSerializers.dll
2019-03-09T22:25:50.1772965+01:00 98,864 1.0.0.0 VRage.Input.dll
2019-03-09T22:25:43.5945257+01:00 732,208 1.0.0.0 VRage.Library.dll
2019-03-09T22:25:43.5955230+01:00 563,760 1.0.0.0 VRage.Math.dll
2019-03-09T22:25:51.2682617+01:00 207,408 VRage.Native.dll
2019-03-09T22:25:51.0197099+01:00 105,008 1.0.0.0 VRage.OpenVRWrapper.dll
2019-03-09T22:25:43.5955230+01:00 357,936 1.0.0.0 VRage.Render.dll
2019-03-09T22:25:43.5955230+01:00 982,064 1.0.0.0 VRage.Render11.dll
2018-03-27T16:51:20.0000000+02:00 77,824 3.0.1.0 WPFLocalizeExtension.dll
2018-01-08T21:35:48.0000000+01:00 27,648 1.2.2 XAMLMarkupExtensions.dll

System.NullReferenceException: Object reference not set to an instance of an object.
at Sandbox.Engine.Voxels.MyPlanetStorageProvider.Init(Int64 seed)
at Sandbox.Engine.Voxels.MyPlanetStorageProvider.Init(Int64 seed, MyPlanetGeneratorDefinition generator, Double radius)
at SEToolbox.Models.StructurePlanetModel.RegeneratePlanet(Int32 seed, Single radius) in D:\Development\GitHub\SEToolbox\Main\SEToolbox\SEToolbox\Models\StructurePlanetModel.cs:line 385
at SEToolbox.ViewModels.StructurePlanetViewModel.RegenerateExecuted() in D:\Development\GitHub\SEToolbox\Main\SEToolbox\SEToolbox\ViewModels\StructurePlanetViewModel.cs:line 185
at SEToolbox.Services.DelegateCommand.Execute() in D:\Development\GitHub\SEToolbox\Main\SEToolbox\SEToolbox\Services\DelegateCommand.cs:line 72
at SEToolbox.Services.DelegateCommand.System.Windows.Input.ICommand.Execute(Object parameter) in D:\Development\GitHub\SEToolbox\Main\SEToolbox\SEToolbox\Services\DelegateCommand.cs:line 154
at MS.Internal.Commands.CommandHelpers.CriticalExecuteCommandSource(ICommandSource commandSource, Boolean userInitiated)
at System.Windows.Controls.MenuItem.InvokeClickAfterRender(Object arg)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)`

Start by reviewing StructurePlanetModel.cs at RegeneratePlanet and StructurePlanetViewModel.cs at RegenerateExecuted, then reproduce resizing with a modded planet using custom voxel or tree textures. Use the reported NullReferenceException in MyPlanetStorageProvider.Init as the failure point. Done means resizing these planets no longer crashes while vanilla planets continue to work.